Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
+1 Swing with caveats Will Swing itself continue to receive serious backing from Oracle? Will they get JavaFX to do everything Swing can and then deprecate Swing (if not officially then in practice?) It really depends on Netbeans. All the L&F issues and other minor ones got attention when Sun began eating its own dogfood and developing Netbeans with Swing. Although having said that is JDeveloper built on top of Swing or SWT - I think probably Swing as JBuilder was so Swing wins whichever tool Oracle eventually standardises on. An example of the point I am trying to make is resolution independence. There was a big push for resolution independence in Swing, which got a long way, but then since JavaFX came along all efforts in that area seem to have been JavaFX focussed. On May 27, 4:32 pm, Sean Devlin wrote: > +1 Swing. There's a ton of documentation out there, and it got some > serious love from Sun between java 5 and 6. > > On May 27, 11:27 am, Laurent PETIT wrote: > > > Although I work with SWT at work, I would say Swing for 2 reasons : > > > * no additional dependency for users of your lib, and *no need* for users > > of your lib to deliver different final apps binaries for different platforms > > * may be easier to work with in your implementation (?) > > > 2010/5/27 Luke VanderHart > > > > My side project is a fairly complex GUI application written in > > > Clojure. Recently, I've become irritated with using Java interop for > > > everything. It's not that Clojure doesn't have nice java interop - it > > > does. It's just that when interacting with a GUI framework, which is a > > > large part of my app, I have to be back in mutable object-oriented > > > land, worrying about class hierarchies, mutable state, locks, etc. > > > Yucky. > > > > So, with a perhaps dangerous lack of sanity and without any guarantee > > > of success, I've decided to try my hand at writing an idiomatic > > > Clojure GUI library. If I have success (which I doubt) I will of > > > course make it available as open source. > > > > I intend for it to be mostly declarative, with a nice DSL for defining > > > GUI elements. Each component will also implement map, and use one of > > > Clojure's reference types as an interface for inspecting / updating > > > its state. I may also implement some aspects of Functional Reactive > > > Programming wherever it's convenient to do so. > > > > What you all must help me decide is what GUI framework to use as the > > > underpinnings of it. It's genuinely hard to decide. I have at least > > > some experience with all of them, so I have no strong preference, but > > > I'd like to get your input. I did consider trying to make it abstract > > > enough that you could plug in *any* of them under the hood, but > > > there's enough differences between the frameworks that that would get > > > very ugly very fast. > > > > Possibilities are: > > > > AWT > > > Pros: native widgets, bundled with Java, low-level > > > Cons: few widgets, considered somewhat obselete > > > > Swing > > > Pros: bundled with Java, good widget selection > > > Cons: non-native widgets > > > > SWT > > > Pros: native widgets, widely used > > > Cons: requires platform-specific libs > > > > QT Jambi > > > Pros: native widgets, huge widget selection, highly-regarded framework > > > Cons: requires platform-specific libs, writing custom widgets is > > > hairy, momentum and support seem to be lagging since Nokia dropped > > > official support. > > > > Remember, the actual API won't matter - that will be completely > > > abstracted away. So try to focus on the framework's look and feel. > > > Also let me know if I've missed any of the framework's key > > > characteristics. > > > > Thanks! > > > > -Luke > > > > -- > > > You received this message because you are subscribed to the Google > > > Groups "Clojure" group. > > > To post to this group, send email to clojure@googlegroups.com > > > Note that posts from new members are moderated - please be patient with > > > your first post. > > > To unsubscribe from this group, send email to > > > clojure+unsubscr...@googlegroups.com > > > For more options, visit this group at > > >http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Rationals, and their size
Ah, thank you - I still shy away from looking into Richs sources, but here it helps: Ratio doesn't have getter for numerator and denominator - they are just public ;-) Being final thats okay of course. So. Whether this helps, I dont know too. I still dont have the lever, but now I have a point to place it at ;-) Regards, alux On 31 Mai, 04:10, ataggart wrote: > Ratio doesn't emit the numerator and > denominator:http://github.com/richhickey/clojure/blob/master/src/jvm/clojure/lang... > > I'm not sure that would help solve your problem, even if it were > available. You either need to turn the ratio into a non-ratio (using > float or double) or use unchecked math functions which are subject to > truncation (e.g., unchecked-multiply). > > On May 30, 1:32 pm, alux wrote: > > > Hello, > > > I careless used rationals in a function, and, well, it took some > > minutes to understand why it was slowing down. (I did this formatting > > by (println (* 1.0 x)) when it started being unreadable - and forgot > > that). > > > I still see rationals as very nice, but try to use them carefully now. > > What I would really like is a possibility to round to a numer of a > > certain size. Like, to an continued fraction of a certain size. But, > > there I need access to the length of numerator and denominator. > > > Now the question - is there any way to access this (or to reach to > > goal of rounding to a rational), that is easier than using the > > BigIntegers myself? > > > Thank you, alux -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
"special form" vs. "macro"
Hi, I got a very basic question about the concept of "special form". What is correct, multiple selections allowed: [ ] A special form is what can be implemented by a macro. [ ] Every macro gives a special form. [ ] Only a macro that doesn't evaluate some of its arguments gives a special form. [ ] A special form is always built in, and cannot be implemented in the language itself. [ ] Special forms are exactly the things that can be called, but dont evaluate all of their arguments. (Macros and build-ins, at least for eager languages.) [ ] The concept of special form doesnt have anything to do with eagerness or lazyness. [ ] You are completely wrong, the right question is: Thank you, alux -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Sina K. Heshmati wrote: > Meikel Brandmeyer wrote: >> Am 30.05.2010 um 16:39 schrieb Sina K. Heshmati: >> > I'll later try to see if I can export datatypes from within a closure. The atomic 'state' doesn't seem to be visible to the datatype methods. The question is why? (defprotocol prot-a (op-a [self x y])) (let [state (atom 10)] (deftype t-a [member] prot-a (op-a [self x y] (+ (.member self) x y @state (def t-a-instance (t-a. 5)) This example is in: http://github.com/sindoc/algorithms/blob/master/src/test/clojure/whiteboard/y2010/hide-adt-state/datatype-in-closure-01.clj Thank you in advance, SinDoc -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Hi,
On May 31, 9:37 am, "Sina K. Heshmati" wrote:
> The atomic 'state' doesn't seem to be visible to the datatype methods. The
> question is why?
>
> (defprotocol prot-a
> (op-a [self x y]))
>
> (let [state (atom 10)]
> (deftype t-a [member]
> prot-a
> (op-a [self x y]
> (+ (.member self) x y @state
>
> (def t-a-instance (t-a. 5))
Of course not. deftype defines a type and not an environment. It's
methods are not closures. (And even if they were, your state would be
the same for all instances.) You have to pass the state as an argument
to the constructor.
(defprotocol prot-a ...)
(deftype t-a [state member] ...)
(defn make-t-a [member] (t-a. (atom 0) member))
(def t-a-instance (make-t-a 5))
If you actually want the same state for instances, use a private var.
(defprotocol prot-a ...)
(def ^{:private true} state (atom 0))
(deftype t-a [member] ...)
(def t-a-instance (t-a. 5))
Sincerely
Meikel
Sincerely
Meikel
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Evaluated once or on each function call?
Is that let expression helps? (let [word (*cfg* :word)] (filter #(= word %) [ "tom" "eat" ])) or this is exactly the same (filter #(= (*cfg* :word) %) [ "tom" "eat" ]) note that *cfg* is a thread binded hash map -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
On 31 May 2010, at 09:35, alux wrote: I got a very basic question about the concept of "special form". What is correct, multiple selections allowed: [ ] A special form is what can be implemented by a macro. Wrong. You cannot implement a Lisp-like language with just macros and functions. At some point the operations defined by macros and functions must be reduced to fundamental operations that are handled directly by the compiler. Example: if and cond. You can implement either one in terms of the other one as a macro, but you cannot implement *both* as macros. [ ] Every macro gives a special form. Wrong. A macro rewrites a form to another form. A special form is interpreted directly by the compiler. There is also a technical difference: a macro is the value of a name, which is looked up in the context of the macro call. Constructs like macrolet (clojure.contrib.macro-utils) permit local macro definitions, for example. A special form is named by a symbol whose interpretation cannot be overridden in any way. [ ] Only a macro that doesn't evaluate some of its arguments gives a special form. Wrong as well. The distinction between macros and special forms is a matter of implementation, not of evaluating arguments. [ ] A special form is always built in, and cannot be implemented in the language itself. True for a minimalist language implementation. An implementation may choose to use more special forms than strictly necessary for performance reasons. [ ] The concept of special form doesnt have anything to do with eagerness or lazyness. True. Konrad. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Evaluated once or on each function call?
On 31 May 2010, at 10:28, Michael Jaaka wrote: Is that let expression helps? (let [word (*cfg* :word)] (filter #(= word %) [ "tom" "eat" ])) or this is exactly the same (filter #(= (*cfg* :word) %) [ "tom" "eat" ]) note that *cfg* is a thread binded hash map The two expressions are equivalent. However, there is a difference when you use let outside of a function definition: (defn filter-words [words] (filter #(= (*cfg* :word) %) words)) This looks the value corresponding to the key :word at each function call. (let [word (*cfg* :word)] (defn filter-words [words] (filter #(= word %) words))) This looks up the value corresponding to :word once, when the function is defined, and uses that same value whenever the function is called. Konrad. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
On May 31, 10:35 am, alux wrote: > [ ] A special form is what can be implemented by a macro. That depends. My understanding is that a special form is something that is "fundamental" to the language, that the evaluator handles as a special case. That is, they need to be implemented in the compiler/ interpreter itself. However, in practice you can't really tell the difference between a macro and a special form, and in fact some Clojure "special forms" are implemented as macros (on top of a "real" special form that is an implementation detail) > > [ ] Every macro gives a special form. Not really. All macros have the same evaluation semantics (macro expansion). > [ ] Only a macro that doesn't evaluate some of its arguments gives a > special form. I don't think evaluation of arguments matters. > > [ ] A special form is always built in, and cannot be implemented in > the language itself. That depends on your point of view, but in general, yes. > > [ ] Special forms are exactly the things that can be called, but dont > evaluate all of their arguments. (Macros and build-ins, at least for > eager languages.) Special forms are special because the evaluator has separate evaluation rules for each of them. Other than that, they are merely another kind of operator (the others being macros and functions) > > [ ] The concept of special form doesnt have anything to do with > eagerness or lazyness. This is correct. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Evaluated once or on each function call?
Hi,
On May 31, 10:43 am, Konrad Hinsen wrote:
> The two expressions are equivalent. However, there is a difference
> when you use let outside of a function definition:
I disagree. The two expressions are not equivalent and you actually
provide the explanation, why they are not. The defn does really make a
difference. (#() is the "defn")
user=> (def *cfg* {:word "tom"})
#'user/*cfg*
user=> (def s (filter #(= (:word *cfg*) %) (list "tom" "eat")))
#'user/s
user=> (def t (let [word (:word *cfg*)] (filter #(= word %) (list
"tom" "eat"
#'user/t
user=> [(first s) (first t)]
["tom" "tom"]
user=> (binding [*cfg* {:word "eat"}] [(fnext s) (fnext t)])
["eat" nil]
Note: I use list instead of the usual vector to avoid chunked seq
evaluation.
Sincerely
Meikel
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Re: Datatype Usage Examples
"Meikel Brandmeyer" said:
> On May 31, 9:37 am, "Sina K. Heshmati" wrote:
>
>> The atomic 'state' doesn't seem to be visible to the datatype methods. The
>> question is why?
>>
>> (defprotocol prot-a
>> (op-a [self x y]))
>>
>> (let [state (atom 10)]
>> (deftype t-a [member]
>> prot-a
>> (op-a [self x y]
>> (+ (.member self) x y @state
>>
>> (def t-a-instance (t-a. 5))
>
> Of course not. deftype defines a type and not an environment. It's
> methods are not closures. (And even if they were, your state would be
> the same for all instances.) You have to pass the state as an argument
> to the constructor.
Now it makes more sense. Thanks.
> (defprotocol prot-a ...)
> (deftype t-a [state member] ...)
>
> (defn make-t-a [member] (t-a. (atom 0) member))
>
> (def t-a-instance (make-t-a 5))
I'll pass.
> If you actually want the same state for instances, use a private var.
>
> (defprotocol prot-a ...)
> (def ^{:private true} state (atom 0))
> (deftype t-a [member] ...)
>
> (def t-a-instance (t-a. 5))
This is a pretty solution but I tested it and it doesn't work the way it
should. That is, when I load [1] in a separate REPL, I can still see and
(reset!) the allegedly private 'state'.
user=> (load-file "path/tp/datatype-01.clj")
#'foo.datatype-01/t-a-instance
user=> (ns PREFIX.datatype-01)
nil
foo.datatype-01 => (op-a t-a-instance 1 2)
18
foo.datatype-01 => state
#
foo.datatype-01 => @state
10
foo.datatype-01 => (reset! state 13)
13
foo.datatype-01 => @state
13
Kind regards,
SinDoc
[1]
http://github.com/sindoc/algorithms/blob/master/src/main/clojure/whiteboard/y2010/hide-adt-state/datatype-01.clj
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Re: Datatype Usage Examples
Hi, On May 31, 10:58 am, "Sina K. Heshmati" wrote: > foo.datatype-01 => (reset! state 13) ^^^ Again: of course you can! You are in the same namespace! In Clojure the "unit" is a namespace and not a type. If you want this level privateness you have to use one namespace per type. However this is not really the Clojure Way. Sincerely Meikel -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
Hello Konrad, many thanks, that clarifies it! So, in "A special form is always built in, and cannot be implemented in the language itself." the first part is true, the second is not. Like most lisps have a bilt in list-reverse for speed reasons. In that case, this build in thing is a special form that can also be implemented in the language (only slow). Right? "A special form is named by a symbol whose interpretation cannot be overridden in any way." This explains the problem from another thread (that made me ask this question in the first place): user=> (def do println) #'user/do ; this uses the special form user=> (do "huhu" "plop") "plop" ; while this uses println user=> ((var do) "huhu" "hello") huhu hello nil Thank you, alux On 31 Mai, 10:38, Konrad Hinsen wrote: > On 31 May 2010, at 09:35, alux wrote: > > > I got a very basic question about the concept of "special form". What > > is correct, multiple selections allowed: > > > [ ] A special form is what can be implemented by a macro. > > Wrong. You cannot implement a Lisp-like language with just macros and > functions. At some point the operations defined by macros and > functions must be reduced to fundamental operations that are handled > directly by the compiler. > > Example: if and cond. You can implement either one in terms of the > other one as a macro, but you cannot implement *both* as macros. > > > [ ] Every macro gives a special form. > > Wrong. A macro rewrites a form to another form. A special form is > interpreted directly by the compiler. > > There is also a technical difference: a macro is the value of a name, > which is looked up in the context of the macro call. Constructs like > macrolet (clojure.contrib.macro-utils) permit local macro definitions, > for example. A special form is named by a symbol whose interpretation > cannot be overridden in any way. > > > [ ] Only a macro that doesn't evaluate some of its arguments gives a > > special form. > > Wrong as well. The distinction between macros and special forms is a > matter of implementation, not of evaluating arguments. > > > [ ] A special form is always built in, and cannot be implemented in > > the language itself. > > True for a minimalist language implementation. An implementation may > choose to use more special forms than strictly necessary for > performance reasons. > > > [ ] The concept of special form doesnt have anything to do with > > eagerness or lazyness. > > True. > > Konrad. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
We would definitely be interested in using something like this for Project Overtone. (http://project-overtone.org) We have already migrated from directly using Swing with the built-in Java interop, to creating a thin layer of clojure functions to trim out the boiler plate, to now wishing we had something more idiomatic. Swing without question. People who are complaining about the look haven't explored what you can do with the pluggable look and feel system. For example, try the demo on the substance page, where they have a variety of different themes implemented: https://substance.dev.java.net/ My guess is that using Swing will get the library used by vastly more applications, because it will be available as a quick GUI for little utilities and sample apps, as well as full fledged applications. Nobody is going to deal with the pain of SWT unless they have a serious app to build, and even then deployment is a total pain. And no, it isn't a one time thing. Dealing with cross platform, native code is an ongoing process that continues to be annoying every time any one of the host platforms upgrades the GUI libraries. Just think, how often does one of windows, mac or linux upgrade the libraries? The much more interesting conversation is about the style of library you are envisioning. Although it would require a small dependency, one thing I would think about doing is using the MigLayout engine for all layout functionality, under the hood. It provides you with the capabilities of all the Swing layout engines, but the interface is straight forward and makes it easy to evolve your GUI overtime without having to keep shifting which type of layout classes you are using. Probably the two key aspects of the library design are going to be the way you register for and handle events, and the way you update widget state. Dangling references to widgets is also a typical source of memory leaks, so finding a way to cleanly keep track of widgets and get rid of them once they are not needed is going to be valuable. In Overtone we have been using a simple event system that lets you register for events (namespaced keywords), and emit them easily. This works pretty well, although it isn't the easiest kind of code to debug. How would a functional reactive style library work? On May 27, 5:18 pm, Luke VanderHart wrote: > My side project is a fairly complex GUI application written in > Clojure. Recently, I've become irritated with using Java interop for > everything. It's not that Clojure doesn't have nice java interop - it > does. It's just that when interacting with a GUI framework, which is a > large part of my app, I have to be back in mutable object-oriented > land, worrying about class hierarchies, mutable state, locks, etc. > Yucky. > > So, with a perhaps dangerous lack of sanity and without any guarantee > of success, I've decided to try my hand at writing an idiomatic > Clojure GUI library. If I have success (which I doubt) I will of > course make it available as open source. > > I intend for it to be mostly declarative, with a nice DSL for defining > GUI elements. Each component will also implement map, and use one of > Clojure's reference types as an interface for inspecting / updating > its state. I may also implement some aspects of Functional Reactive > Programming wherever it's convenient to do so. > > What you all must help me decide is what GUI framework to use as the > underpinnings of it. It's genuinely hard to decide. I have at least > some experience with all of them, so I have no strong preference, but > I'd like to get your input. I did consider trying to make it abstract > enough that you could plug in *any* of them under the hood, but > there's enough differences between the frameworks that that would get > very ugly very fast. > > Possibilities are: > > AWT > Pros: native widgets, bundled with Java, low-level > Cons: few widgets, considered somewhat obselete > > Swing > Pros: bundled with Java, good widget selection > Cons: non-native widgets > > SWT > Pros: native widgets, widely used > Cons: requires platform-specific libs > > QT Jambi > Pros: native widgets, huge widget selection, highly-regarded framework > Cons: requires platform-specific libs, writing custom widgets is > hairy, momentum and support seem to be lagging since Nokia dropped > official support. > > Remember, the actual API won't matter - that will be completely > abstracted away. So try to focus on the framework's look and feel. > Also let me know if I've missed any of the framework's key > characteristics. > > Thanks! > > -Luke -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/
Re: "special form" vs. "macro"
On 31 May 2010, at 11:08, alux wrote: Hello Konrad, many thanks, that clarifies it! So, in "A special form is always built in, and cannot be implemented in the language itself." the first part is true, the second is not. Like most lisps have a bilt in list-reverse for speed reasons. In that case, this build in thing is a special form that can also be implemented in the language (only slow). Right? Right. "A special form is named by a symbol whose interpretation cannot be overridden in any way." This explains the problem from another thread (that made me ask this question in the first place): user=> (def do println) #'user/do ; this uses the special form user=> (do "huhu" "plop") "plop" ; while this uses println user=> ((var do) "huhu" "hello") huhu hello nil Yes, that illustrates the handling of special forms nicely. Note that it is somewhat specific to Clojure. Other Lisps handle the mapping from symbols to functions/macros/special forms differently. One more variant is helpful: user=> (user/do "huhu" "hello") huhu hello nil This illustrates that special forms need to be identified by an unqualified symbol in the operator position. Another detail that is good to know is that syntax-quote (`) knows about special forms and treats their symbols specially even if they are not in the operator position: user=> (declare do foo) #'user/foo user=> `do do user=> `foo user/foo Konrad. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Evaluated once or on each function call?
On 31 May 2010, at 10:53, Meikel Brandmeyer wrote: The two expressions are equivalent. However, there is a difference when you use let outside of a function definition: I disagree. The two expressions are not equivalent and you actually provide the explanation, why they are not. The defn does really make a difference. (#() is the "defn") Oops... Right, I didn't see the #! Konrad. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
How to make that eval could see its caller context
Hello, I would like to make that eval see context of the caller block. In the example: (defn my-if [a b c] (let [z (name (gensym)) t (symbol (str z "true")) f (symbol (str z "false")) ] (def t (fn[] b)) (def f (fn[] c)) (def mycond (boolean a)) ((eval (symbol (str z mycond)) the symbol can't be found in context represented by the eval. What to do to make it working? Thanks, -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Evaluated once or on each function call?
Thanks, I just wanted to know if keyword hashmap is evaluated on each time. You have answered my question. Thanks again. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
RE: "special form" vs. "macro"
"alux" said: > I got a very basic question about the concept of "special form". What > is correct, multiple selections allowed: > > [ ] A special form is what can be implemented by a macro. Wrong. Macros cannot remove the need for special-forms, at least not in a real interpreter. In a metacircular implementation, you can replace special-forms with calls to the base-level implementation. For instance, if you evaluate 'if' at base-level, then you can use it to define 'cond' at base-level. > [ ] Every macro gives a special form. They can all be reduced to a number of expressions that cannot be implemented by neither macros nor functions. These expressions can be evaluated using normal functions if you have lazy evaluation of arguments. So, if you have lazy-eval, there's no need for special-forms. > [ ] Only a macro that doesn't evaluate some of its arguments gives a > special form. You could say that. > [ ] A special form is always built in, and cannot be implemented in > the language itself. Unless you have lazy-eval. > [ ] Special forms are exactly the things that can be called, but dont > evaluate all of their arguments. (Macros and build-ins, at least for > eager languages.) > > [ ] The concept of special form doesnt have anything to do with > eagerness or lazyness. Wrong. It has everything to do with laziness. If you have one, you don't need the other. Please note that, the concept of special-forms is a compromise and I don't think anyone would want to have them. A language designer has to make a choice as to whether to have special forms or not. If they don't want special-forms, then they should provide lazy evaluation of arguments. Some introduce functional parameters in order to provide lazy evaluation of arguments but that choice has its own trade-offs since it introduces a kind of dynamic scoping. Kind regards, SinDoc -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
RE: "special form" vs. "macro"
"Sina K. Heshmati" said: > "alux" said: > >> I got a very basic question about the concept of "special form". What >> is correct, multiple selections allowed: >> >> [ ] A special form is what can be implemented by a macro. > > Wrong. Macros cannot remove the need for special-forms, at least not in a real > interpreter. In a metacircular implementation, you can replace special-forms > with > calls to the base-level implementation. For instance, if you evaluate 'if' at > base-level, then you can use it to define 'cond' at base-level. Oh, I meant: ... then you can use it to define 'cond' at *meta*-level. >> [ ] Every macro gives a special form. > > They can all be reduced to a number of expressions that cannot be implemented > by > neither macros nor functions. > > These expressions can be evaluated using normal functions if you have lazy > evaluation of arguments. So, if you have lazy-eval, there's no need for > special-forms. > >> [ ] Only a macro that doesn't evaluate some of its arguments gives a >> special form. > > You could say that. > >> [ ] A special form is always built in, and cannot be implemented in >> the language itself. > > Unless you have lazy-eval. > >> [ ] Special forms are exactly the things that can be called, but dont >> evaluate all of their arguments. (Macros and build-ins, at least for >> eager languages.) >> >> [ ] The concept of special form doesnt have anything to do with >> eagerness or lazyness. > > Wrong. It has everything to do with laziness. If you have one, you don't need > the > other. > > Please note that, the concept of special-forms is a compromise and I don't > think > anyone would want to have them. A language designer has to make a choice as to > whether to have special forms or not. If they don't want special-forms, then > they > should provide lazy evaluation of arguments. > > Some introduce functional parameters in order to provide lazy evaluation of > arguments but that choice has its own trade-offs since it introduces a kind of > dynamic scoping. > > Kind regards, > SinDoc -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: How to make that eval could see its caller context
On May 31, 12:03 pm, Michael Jaaka wrote: > Hello, > > I would like to make that eval see context of the caller block. > In the example: > > (defn my-if [a b c] > (let [z (name (gensym)) t (symbol (str z "true")) f (symbol (str z > "false")) ] > (def t (fn[] b)) > (def f (fn[] c)) > (def mycond (boolean a)) > ((eval (symbol (str z mycond)) > > the symbol can't be found in context represented by the eval. What to > do to make it working? Practically all of the time you need to solve this kind of problem, you can use a map with symbol -> value pairs instead of adding bunch of variable definitions to the environment. And it usually turns out once you do this you don't even need to (eval) anything anymore. You also *really* do not want to redefine globals in a function body if you have any pretense of doing functional code. Why don't you use (let []) instead? Joost. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: How to make that eval could see its caller context
Well, this is just an example. I need to refer to global vars from eval. One solution is to define these vars in eval form, but I would like to omit that step. On 31 Maj, 12:53, Joost wrote: > On May 31, 12:03 pm, Michael Jaaka > wrote: > > > Hello, > > > I would like to make that eval see context of the caller block. > > In the example: > > > (defn my-if [a b c] > > (let [z (name (gensym)) t (symbol (str z "true")) f (symbol (str z > > "false")) ] > > (def t (fn[] b)) > > (def f (fn[] c)) > > (def mycond (boolean a)) > > ((eval (symbol (str z mycond)) > > > the symbol can't be found in context represented by the eval. What to > > do to make it working? > > Practically all of the time you need to solve this kind of problem, > you can use a map with symbol -> value pairs instead of adding bunch > of variable definitions to the environment. And it usually turns out > once you do this you don't even need to (eval) anything anymore. > > You also *really* do not want to redefine globals in a function body > if you have any pretense of doing functional code. Why don't you use > (let []) instead? > > Joost. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: How to make that eval could see its caller context
On May 31, 1:11 pm, Michael Jaaka wrote: > Well, this is just an example. > I need to refer to global vars from eval. You can do that already: user> (def bla "foo bar") #'user/bla user> bla "foo bar" user> (eval 'bla) "foo bar" user> It's just not a good idea. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: How to make that eval could see its caller context
Hmmm, I have just missed on thing. The problems comes when evaluation is in another thread. (defn sleep[n] (Thread/sleep n)) (future (eval (load-string "((fn[] (sleep 100) (println \"wowo\")) )") )) The solution is: (defn sleep[n] (Thread/sleep n)) (let [a (get-thread-bindings) ] (future (with-bindings a (eval (load-string "((fn[] (sleep 100) (println \"wowo\")) )") I will try it on my code. Thanks anyway! -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
"Meikel Brandmeyer" said: > On May 31, 10:58 am, "Sina K. Heshmati" wrote: > >> foo.datatype-01 => (reset! state 13) > ^^^ > > Again: of course you can! You are in the same namespace! In Clojure > the "unit" is a namespace and not a type. If you want this level > privateness you have to use one namespace per type. However this is > not really the Clojure Way. Here's my concern: - My program (A) is running. - B is running on the same VM. - B accesses the state of A. - B alters the state of A in an inconsistent way e.g. whenever the internal state x changes, the internal state y also has to change accordingly, but B only changes x. - A is screwed. The author of Clojure calls encapsulation a folly but I don't understand why (?) How can we avoid situations like the one explained above? I came up with the following, which does what I want by relying on the lexical scope of functions. This is OK but the only problem is the fact that I have to hardcode function calls for each type method. (defprotocol prot-a (op-a [self x y])) (let [state (atom 10)] (defn op-a [self x y] (+ x y (.member self) @state))) (deftype t-a [member] prot-a (op-a [self x y] (op-a self x y))) (def t-a-1 (t-a. 5)) Is there a way to pass the function itself rather than making a new function that calls the exact same function with the same arguments? Kind regards, SinDoc -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Hi,
On May 31, 1:46 pm, "Sina K. Heshmati" wrote:
> Here's my concern:
>
> - My program (A) is running.
> - B is running on the same VM.
> - B accesses the state of A.
> - B alters the state of A in an inconsistent way
> e.g. whenever the internal state x changes, the
> internal state y also has to change accordingly,
> but B only changes x.
> - A is screwed.
A is namespace my.ns.a. There you define a private var: (def
^{:private true} state (atom 0)). B is namespace my.ns.b. B cannot
change state in A.
user=> (ns my.ns.a)
nil
my.ns.a=> (def ^{:private true} state (atom 0))
#'my.ns.a/state
my.ns.a=> (ns my.ns.b)
nil
my.ns.b=> (reset! my.ns.a/state :messed-up-your-state-harharhar)
java.lang.IllegalStateException: var: my.ns.a/state is not public
(NO_SOURCE_FILE:4)
>From a philosophical point of view:
Either you develop an application and
you are in charge of B. => You are in control: don't do it.
you are not in charge of B. => B is obviously a crappy library which
you should not use in project.
You develop a library: A. Why bother? Since your library is well
documented it clearly defines the contract. Why care for people who
are too lazy to read?
> Is there a way to pass the function itself rather
> than making a new function that calls the exact
> same function with the same arguments?
(let [state (atom 0)]
(extend t-a
prot-a
{:op-a (fn [this x y] (+ (.member this) x y @state))}))
Sincerely
Meikel
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Modify clojure startup behavior
I'd like to have clojure *not* `(load x)` where x is at least: clojure.zip, clojure.xml, clojure.set when starting clojure up. I didn't really find any place in the clojure code where I could do that except remove the entire subsystem from the ant build.xml. Anyone knows how to solve this? Is there some file which is responsible for initializing clojure? -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Problem solved, see below.
Meikel Brandmeyer wrote:
> On May 31, 1:46 pm, "Sina K. Heshmati" wrote:
>
>> Here's my concern:
>>
>> - My program (A) is running.
>> - B is running on the same VM.
>> - B accesses the state of A.
>> - B alters the state of A in an inconsistent way
>> e.g. whenever the internal state x changes, the
>> internal state y also has to change accordingly,
>> but B only changes x.
>> - A is screwed.
>
> A is namespace my.ns.a. There you define a private var: (def
> ^{:private true} state (atom 0)). B is namespace my.ns.b. B cannot
> change state in A.
>
> user=> (ns my.ns.a)
> nil
> my.ns.a=> (def ^{:private true} state (atom 0))
> #'my.ns.a/state
> my.ns.a=> (ns my.ns.b)
> nil
> my.ns.b=> (reset! my.ns.a/state :messed-up-your-state-harharhar)
> java.lang.IllegalStateException: var: my.ns.a/state is not public
> (NO_SOURCE_FILE:4)
>
> From a philosophical point of view:
> Either you develop an application and
> you are in charge of B. => You are in control: don't do it.
> you are not in charge of B. => B is obviously a crappy library which
> you should not use in project.
>
> You develop a library: A. Why bother? Since your library is well
> documented it clearly defines the contract. Why care for people who
> are too lazy to read?
True but my main concern is security of a running application. It could very
well be that B is just a bunch of interactions, in which case B can enter A's
namespace.
I still haven't tried to use reflection to see if I can still access the state.
In case a program can use metaprogramming to access private fields of an
abstraction, no matter what the programmer does, then my concerns are not
relevant.
>> Is there a way to pass the function itself rather
>> than making a new function that calls the exact
>> same function with the same arguments?
>
> (let [state (atom 0)]
> (extend t-a
> prot-a
> {:op-a (fn [this x y] (+ (.member this) x y @state))}))
Thanks a bunch, Meikel.
Problem solved. Please see:
http://github.com/sindoc/algorithms/blob/master/src/main/clojure/whiteboard/y2010/hide-adt-state/datatype-and-closure-01.clj
Kind regards,
SinDoc
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Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
+1 for swing On Thu, May 27, 2010 at 8:48 PM, Luke VanderHart wrote: > My side project is a fairly complex GUI application written in > Clojure. Recently, I've become irritated with using Java interop for > everything. It's not that Clojure doesn't have nice java interop - it > does. It's just that when interacting with a GUI framework, which is a > large part of my app, I have to be back in mutable object-oriented > land, worrying about class hierarchies, mutable state, locks, etc. > Yucky. > > So, with a perhaps dangerous lack of sanity and without any guarantee > of success, I've decided to try my hand at writing an idiomatic > Clojure GUI library. If I have success (which I doubt) I will of > course make it available as open source. > > I intend for it to be mostly declarative, with a nice DSL for defining > GUI elements. Each component will also implement map, and use one of > Clojure's reference types as an interface for inspecting / updating > its state. I may also implement some aspects of Functional Reactive > Programming wherever it's convenient to do so. > > What you all must help me decide is what GUI framework to use as the > underpinnings of it. It's genuinely hard to decide. I have at least > some experience with all of them, so I have no strong preference, but > I'd like to get your input. I did consider trying to make it abstract > enough that you could plug in *any* of them under the hood, but > there's enough differences between the frameworks that that would get > very ugly very fast. > > Possibilities are: > > AWT > Pros: native widgets, bundled with Java, low-level > Cons: few widgets, considered somewhat obselete > > Swing > Pros: bundled with Java, good widget selection > Cons: non-native widgets > > SWT > Pros: native widgets, widely used > Cons: requires platform-specific libs > > QT Jambi > Pros: native widgets, huge widget selection, highly-regarded framework > Cons: requires platform-specific libs, writing custom widgets is > hairy, momentum and support seem to be lagging since Nokia dropped > official support. > > Remember, the actual API won't matter - that will be completely > abstracted away. So try to focus on the framework's look and feel. > Also let me know if I've missed any of the framework's key > characteristics. > > Thanks! > > -Luke > > > > > > > > > > > > > > > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with your > first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: special forms and let binding
In fact, keywords are not symbols. So thats why you were wrong. You can read about in on the page http://clojure.org/lisps -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Hi, On May 31, 3:15 pm, "Sina K. Heshmati" wrote: > True but my main concern is security of a running application. > It could very well be that B is just a bunch of interactions, > in which case B can enter A's namespace. ??? I'm not sure I understand. How can B "enter" the namespace of A? If you mean you have a Repl and someone arbitrary can enter commands there as she likes... You can always mess up everything. > I still haven't tried to use reflection to see if I can still > access the state. In case a program can use metaprogramming > to access private fields of an abstraction, no matter what the > programmer does, then my concerns are not relevant. To be honest: I don't see the problem. You talk about a very fuzzy "the user might do something". Do you have a particular scenario in mind? > Problem solved. Just some minor remarks: you can move the extend outside the let and the declare is not necessary. defprotocol will take care of that for you. Sincerely Meikel -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
in case, you want to abstract over swing ... there is this guy from germany: Karsten Lentzsch. he is author of http://www.jgoodies.com/ and has incredible knowledge about swing and esp. in abstracting over swing. He knows all the strongs and weaknesses of swing and beeing involved in http://www.jgoodies.com/articles/jsr296_de.pdf he tried to move things forward but was not very lucky doing so - according to his presentation at the wjax munich in Oktober last year. maybe Karsten could be asked for his expertise ... -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
[ANN]: Google Chrome extension for TryClojure (try-clojure.org)
Hi all, I made a little extension for google chrome. It allows to start try- clojure REPL via clicking on toolbar button. Also it grabs selected text and evaluates it in REPL. Feel free to comment, report bugs and suggestions. /Sergey -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Multithreading didn't make my program as much faster as I expected...
On 31 May 2010 06:12, Zak Wilson wrote: > The trouble with pmap is that it only works well with a slow function > and a short sequence. In trivial tests, it seems to be best if the > sequence has as many elements as you do cores. > > I've been experimenting with things that are like pmap, but work > better in situations that I care about. I'm having trouble getting > full performance out of a quad-core machine, but dual-core is working > pretty well so far. Here's some discussion with a link to sample code: > http://groups.google.com/group/clojure/browse_thread/thread/963cdb76f0c3c178 > > And here's my personal utility file containing mostly re- > implementations of things I didn't know where to find. The zpmap > function is an eager parallel map that works well on large vectors and > maps with a fairly fast function: > http://github.com/zakwilson/zutil-clj/blob/master/util.clj Interesting! Reducing the number of parallel threads in my test case from 10 to 2 improved the speed of the test from 12 seconds to 10, which is about as good as can be expected. And it immediately steps back up to 12 seconds when I use 3 threads. So for CPU intensive tasks, it seems that having precisely the same number of threads as CPUs gives the best performance. It looks like Java schedules 1 thread per CPU, until it can't, and at that point scheduling overhead kicks in (costing something like 30% performance). How did you arrive at the "number of CPUs + 2" approach in zpmap? I'd have thought that the +2 would hurt performance as it did in my case. So even when Clojure makes threading as easy as possible, it's still complicated in subtle ways. Ah, well :-) Thanks for the help. Paul. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Clojure script with shebangoid on windows
On 31 May 2010 07:48, alux wrote: > Hello Glen, good hint. Problem and solution reproduced ;-) Yes, it looks like Clojure's (comment ...) form requires the contents of the comment to be syntactically correct Clojure forms. As Glen says, forward slashes seem to work - although personally, I dislike being forced to use forward slashes on Windows :-( Is there a multi-line comment form in Clojure that can contain arbitrary text? Paul. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
java.lang.Boolean cannot be cast to clojure.lang.IFn
Hi, I've started learn Clojure. While I am writing some functions I was getting the java.lang.Boolean cannot be cast to clojure.lang.IFn. I was wondering if somebody could help me to move on: ; for testing (def sudoku ( sorted-map '[1 1] '(98) '[1 2] '(123) '[2 1] '(56789) '[2 2] '(456))) (def vall 4) (def poss (vector [1 1] [1 2])) (defn valueIn [map value positions] (loop [start (first positions) end (rest positions) cont false] (if (or (true? cont) (nil? start)) cont (recur (cont (contains? (get map start) value)) (start (first end)) (end (rest end)) The call=> (valueIn(sudoku vall poss) gives me the above error. Thank you, -- Gary -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
+1 swing. Even if the resulting applications are as ugly as sin, a working, idiomatic implementation gives us a reference point from which to dream up better futures. On Sun, May 30, 2010 at 10:38 PM, Antony Blakey wrote: > > On 31/05/2010, at 2:27 PM, James Cunningham wrote: > >> >> >> On May 30, 9:23 pm, Antony Blakey wrote: >>> I care about Mac and Windows primarily, and building software that will >>> sell (not dev tools) requires good native look and feel. >> >> Do you have a single example of an SWT app that has a decent feel on >> OS X? I've spent a fair amount of time with Eclipse lately, and--- >> frankly---it feels about as native as an Alabaman in Nice. No native >> toolbar, no native tabs, slower and uglier than either Netbeans or >> Intellij. My only other experience with an SWT app was entirely >> negative from a performance and look-and-feel perspective (Vuze). > > Vuze looks OK to me in the 5 minutes I've just spent. In any case, my opinion > comes from doing parallel GUI development in IB and SWT to see if I could use > Clojure/SWT rather than MacRuby (XCode/IB). I'm not using the RCP which > imprints it's own not-really-OSX flavour in spite of the widgets. > > You have to do more than just use SWT to get a Mac application to feel right, > and one's GUI layout code needs to be parametric and rules based, rather than > just swapping the L&F. That said, it's still easier than writing three UIs. > > Antony Blakey > - > CTO, Linkuistics Pty Ltd > Ph: 0438 840 787 > > The intuitive mind is a sacred gift and the rational mind is a faithful > servant. We have created a society that honours the servant and has forgotten > the gift. > -- Albert Einstein > > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with your > first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
Let the best decider of a GUI toolkit be based on pragmatism and design philosophy. To that end Swing wins. Clojure runs on JVM and takes advantage of anything Java that it does not provide for in a Lispy way. Swing is just another one of those things automatically there, which can have a nice layer to make it more useful, interesting. Clojure does not include any extra libraries, except ASM, to operate. Won't need any extra ones by using a Swing-based layer. Clojure is completely cross-platform with supported OS for Java. A Swing layer will be also. Clojure can already create simple GUIs with Swing in a few lines of code. It can only get better with a dedicated layer. Swing is already a good selling point for Clojure. It actually is promoting Clojure to have read Swing support intrinsically. You cannot say these things about any other toolkit at this time. I am willing to do some work on the Swing layer, if it is wanted. If others want to work on SWT, Tk, etc. they can do that. That's what it comes down to, where the effort is put. I will step up to put some of mine behind the Swing-based one, anybody else? Voting and debating points are okay, but results are better. Swing is already a result, a layer is just furthering it. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: (apply interleave [[1 2]])
Makes sense. -- Paul Hobbs On Sat, May 29, 2010 at 11:51 PM, Eugen Dück wrote: > Paul, > > I already gave a minimal example of the code it makes simpler, i.e. > work in the first place: > > (apply interleave some-colls) > > I ran into this a couple of times, and wrote my own variant of > interleave that handles the one-coll case. I'd rather see this case > handled by interleave. > > How often do you do: > > (+ 5) > > or > > (* 3) > > ? But you might have used something like > > (apply + coll) > > or > > (reduce + coll) > > and under certain circumstances your coll might have had only one > element. Still + works just fine and returns a value that makes sense > (it even does if you call it with no argument). I'm basically asking > to get the same case that clojure handles for a lot of other functions > added to "interleave". > > Eugen > > On May 29, 7:07 pm, Paul Hobbs wrote: > > What code would this make simpler? Are you constantly having to check > this > > > > (apply interleave some-colls) > > > special case? If not, I don't see a reason to include it. > > -- > > Paul Hobbs > > > > On Sat, May 29, 2010 at 1:32 AM, Eugen Dück wrote: > > > When I do > > > > > (apply interleave some-colls) > > > > > and some-colls is a sequence/collection of only one sequence/ > > > collection, it will throw: > > > > > user=> (apply interleave [[1 2]]) > > > java.lang.IllegalArgumentException: Wrong number of args passed to: > > > core$interleave (NO_SOURCE_FILE:0) > > > > > (Of course I don't need the apply to cause that exception, but calling > > > interleave directly with just one parameter doesn't make any sense. > > > But in the case you use apply, having only one sequence in a sequence > > > is a possible corner case that can arise "at run time") > > > > > In order to make interleave more general, I'd like to add a "one param > > > overload" to interleave like > > > > > (defn interleave > > > "Returns a lazy seq of the first item in each coll, then the second > > > etc." > > > ([c] (seq c)) > > > ... > > > > > or even just > > > > > (defn interleave > > > ([c] c) > > > > > but that would break the contract of interleave, in that it returns > > > whatever you pass in, which might not be a sequence, as is the case in > > > my example. > > > > > Any thoughts on this? > > > > > Eugen > > > > > -- > > > You received this message because you are subscribed to the Google > > > Groups "Clojure" group. > > > To post to this group, send email to clojure@googlegroups.com > > > Note that posts from new members are moderated - please be patient with > > > your first post. > > > To unsubscribe from this group, send email to > > > clojure+unsubscr...@googlegroups.com > > > > > > For more options, visit this group at > > >http://groups.google.com/group/clojure?hl=en > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Modify clojure startup behavior
On 2010/05/31 14:25, MHOOO wrote: > I'd like to have clojure *not* `(load x)` where x is at least: > clojure.zip, clojure.xml, clojure.set > when starting clojure up. I didn't really find any place in the > clojure code where I could do that except remove the entire subsystem > from the ant build.xml. > Anyone knows how to solve this? Is there some file which is > responsible for initializing clojure? It isn't a very pretty way but you can simply remove the load statements from RT.java around line 415. That works fine. If you really need any of them later, you can still use/require/load them. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
Maybe Clojure uses the term "special form" differently than Common Lisp does, but here's how to think of "special form" in the Common Lisp sense. A form that is *NOT* a special form like (F A B C D ...) will either evaluate: 1. (SYMBOL-FUNCTION F), then A, B, C, D, ... in order from left-to- right, OR 2. A, B, C, D, ... in order from left-to-right then (SYMBOL-FUNCTION F) And, cannot change the lexical environment (add or remove symbols in the environment). It is up to the implementation whether (SYMBOL-FUNCTION F) gets evaluated first or last, but A, B, C, D, ... get evaluated from let to right in order before F is invoked. Any form that does not ALWAYS obey that is a "special form". Examples: (+ 3 5 (+ 6 7) ii), the form 3 is evaluated, then 5, then (+ 6 7), then ii, then all of these are passed to (SYMBOL-FUNCTION +) to execute. This IS NOT a special form. (IF A B C) does not evaluate both B and C. Thus, it IS a special form. The following IS NOT a special form (as long as XX and YY aren't dynamic variables that we're overriding but rather just local variables here like it looks) because it always evaluates A and B in the expected order: (DEFMACRO WEIRD (A B) `(LET ((XX ,A)) (LET ((YY ,B)) (DO-SOMETHING (+ XX YY) (- XX YY) (WEIRD (+ 6 7) ii) The following IS a special form because it does not evaluate A and B in the expected order: (DEFMACRO WEIRD-SPECIAL (A B) `(LET ((YY ,B)) (LET ((XX ,A)) (DO-SOMETHING (+ XX YY) (- XX YY) (WEIRD-SPECIAL (+ 6 7) ii) The following IS also a special form since it doesn't always evaluate A and B in the expected order: (DEFMACRO WEIRD-MAY-BE-SPECIAL (SPECIAL A B) `(IF ,SPECIAL (LET ((XX ,A)) (LET ((YY ,B)) (DO-SOMETHING (+ XX YY) (- XX YY (LET ((YY ,B)) (LET ((XX ,A)) (DO-SOMETHING (+ XX YY) (- XX YY) (WEIRD-MAY-BE-SPECIAL (ZEROP (RANDOM 2)) (+ 6 7) ii) The term "special form" (at least in Common Lisp) has nothing to do with whether it is built-in or user-defined. It has to do with whether or not all of its components are evaluated in the expected order. ttyl, Patrick -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
That was interesting. One more Q. What determines whether special forms can be used in functions eg you can't def a variable in a fn. Is it there some rule or is it special form specific depending on (a) the intended use of the special form (b) the mechanics of getting the compiler to use the special form On May 31, 9:48 am, Jarkko Oranen wrote: > On May 31, 10:35 am, alux wrote: > > > [ ] A special form is what can be implemented by a macro. > > That depends. My understanding is that a special form is something > that is "fundamental" to the language, that the evaluator handles as a > special case. That is, they need to be implemented in the compiler/ > interpreter itself. However, in practice you can't really tell the > difference between a macro and a special form, and in fact some > Clojure "special forms" are implemented as macros (on top of a "real" > special form that is an implementation detail) > > > > > [ ] Every macro gives a special form. > > Not really. All macros have the same evaluation semantics (macro > expansion). > > > [ ] Only a macro that doesn't evaluate some of its arguments gives a > > special form. > > I don't think evaluation of arguments matters. > > > > > [ ] A special form is always built in, and cannot be implemented in > > the language itself. > > That depends on your point of view, but in general, yes. > > > > > [ ] Special forms are exactly the things that can be called, but dont > > evaluate all of their arguments. (Macros and build-ins, at least for > > eager languages.) > > Special forms are special because the evaluator has separate > evaluation rules for each of them. Other than that, they are merely > another kind of operator (the others being macros and functions) > > > > > [ ] The concept of special form doesnt have anything to do with > > eagerness or lazyness. > > This is correct. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
On May 31, 4:35 pm, Quzanti wrote: > That was interesting. > > One more Q. > > What determines whether special forms can be used in functions eg you > can't def a variable in a fn. You can: user> (defn fun [v] (def my-v v)) user> (fun 'a) user> my-v a user> (fun 'b) user> my-v b I'm not aware of any special form that can't be used inside a function. But I haven't looked for them either. > Is it there some rule or is it special form specific depending on > (a) the intended use of the special form > (b) the mechanics of getting the compiler to use the special form First you'd have to find such special forms. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: java.lang.Boolean cannot be cast to clojure.lang.IFn
On May 31, 2:11 pm, garyk wrote: > Hi, > I've started learn Clojure. While I am writing some functions I was > getting the java.lang.Boolean cannot be cast to clojure.lang.IFn. I > was wondering if somebody could help me to move on: > > ; for testing > (def sudoku ( sorted-map '[1 1] '(98) '[1 2] '(123) '[2 1] '(56789) > '[2 2] '(456))) > (def vall 4) > (def poss (vector [1 1] [1 2])) > > (defn valueIn [map value positions] > (loop [start (first positions) end (rest positions) cont false] > (if (or (true? cont) (nil? start)) > cont > (recur (cont (contains? (get map start) value)) (start (first > end)) (end (rest end)) recur takes positional arguments, not (key value) "pairs" (which aren't pairs, but function calls). You want *something* like (recur (first end) (rest end) (contains? (get map start) value)) but I can't really make heads or tails out of your code. Note that '(56789) is a list of ONE number, while it looks like you're expecting it to be a list of digits - that would be '(5 6 7 8 9) -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: java.lang.Boolean cannot be cast to clojure.lang.IFn
Oh, and you code throws "clojure.lang.PersistentVector cannot be cast to java.lang.Number [Thrown class java.lang.ClassCastException]" for me. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
We are willing to put some time into this at our end. We are in the process of replacing our Java desktop apps by Clojure apps. Removing Java code is a mid-term goal that we want to keep in our scope as we move on. Anything to reduce code size is a welcomed. How and when do we start this ? Luc P. laseray wrote .. > Let the best decider of a GUI toolkit be based on pragmatism and > design philosophy. > > To that end Swing wins. > > Clojure runs on JVM and takes advantage of anything Java that it does > not provide for in a Lispy way. > Swing is just another one of those things automatically there, which > can have a nice layer to make it more useful, interesting. > > Clojure does not include any extra libraries, except ASM, to operate. > Won't need any extra ones by using a Swing-based layer. > > Clojure is completely cross-platform with supported OS for Java. A > Swing layer will be also. > > Clojure can already create simple GUIs with Swing in a few lines of > code. It can only get better with a dedicated layer. > > Swing is already a good selling point for Clojure. It actually is > promoting Clojure to have read Swing support intrinsically. > > You cannot say these things about any other toolkit at this time. > > I am willing to do some work on the Swing layer, if it is wanted. If > others want to work on SWT, Tk, etc. they can do that. > That's what it comes down to, where the effort is put. > > I will step up to put some of mine behind the Swing-based one, anybody > else? > > Voting and debating points are okay, but results are better. Swing is > already a result, a layer is just furthering it. > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with your > first > post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: java.lang.Boolean cannot be cast to clojure.lang.IFn
On Mon, May 31, 2010 at 14:11, garyk wrote: > Hi, > I've started learn Clojure. While I am writing some functions I was > getting the java.lang.Boolean cannot be cast to clojure.lang.IFn. I > was wondering if somebody could help me to move on: > > ; for testing > (def sudoku ( sorted-map '[1 1] '(98) '[1 2] '(123) '[2 1] '(56789) > '[2 2] '(456))) > (def vall 4) > (def poss (vector [1 1] [1 2])) > > > (defn valueIn [map value positions] > (loop [start (first positions) end (rest positions) cont false] > (if (or (true? cont) (nil? start)) > cont > (recur (cont (contains? (get map start) value)) (start (first > end)) (end (rest end)) Your (recur ...) is completely mixed up. The specific error you are seeing is because of the subexpression: (cont (contains? ...)) which attempts to apply cont as a function to the result of the call to (contains? ...). cont isn't a function, it's a boolean value (you gave it the value false at the start of the loop). > The call=> (valueIn(sudoku vall poss) gives me the above error. > > Thank you, > -- Gary > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with your > first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Meikel Brandmeyer wrote: > On May 31, 3:15 pm, "Sina K. Heshmati" wrote: > >> True but my main concern is security of a running application. >> It could very well be that B is just a bunch of interactions, >> in which case B can enter A's namespace. > > ??? I'm not sure I understand. How can B "enter" the namespace > of A? If you mean you have a Repl and someone arbitrary can > enter commands there as she likes... You can always mess up > everything. > >> I still haven't tried to use reflection to see if I can still >> access the state. In case a program can use metaprogramming >> to access private fields of an abstraction, no matter what the >> programmer does, then my concerns are not relevant. > > To be honest: I don't see the problem. You talk about a very > fuzzy "the user might do something". Do you have a particular > scenario in mind? You're right. It's rather a contract problem as you said than a security concern because no matter what we do, people can use reflection to mess things up anyway. I'm likely to drop the whole idea of encapsulating the state in a closure and rely on private annotations. Thanks Meikel for bearing with me :) >> Problem solved. > > Just some minor remarks: you can move the extend outside the > let and the declare is not necessary. defprotocol will take > care of that for you. Nice. That's much better. I'd like to thank Meikel, Krukow, and Adrian for participating in this discussion. Kind regards, SinDoc -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Multithreading didn't make my program as much faster as I expected...
Number of CPUs + 2 is what pmap uses, and I assumed the idea was to keep all the CPUs busy in the event that one finishes before the others. I wrote it before I did testing with npmap. Since reading your last post, I did a bit of testing with modified versions of zpmap and found that it isn't making much difference on a quad-core machine. It might be a few ms faster on a 3.5s call, but it's so close that it's probably within the margin of error. It may turn out to be a better approach to rewrite pmap instead of wrapping it. I'm wondering if the attempt to make it both semi-lazy and parallel isn't optimal for speed. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
Are you sure that always works? I think I am misunderstanding Halloway's Taxonomy of Macro's chapter defstruct is written as a macro and Stuart then comments "This macro looks so simple that you may be tempted to try to write it as a function. You won't be able to because def is a special form. You must generate def at macro time; you cannot make 'dynamic' calls to def at runtime" On May 31, 4:05 pm, Joost wrote: > On May 31, 4:35 pm, Quzanti wrote: > > > That was interesting. > > > One more Q. > > > What determines whether special forms can be used in functions eg you > > can't def a variable in a fn. > > You can: > > user> (defn fun [v] (def my-v v)) > user> (fun 'a) > user> my-v > a > user> (fun 'b) > user> my-v > b > > I'm not aware of any special form that can't be used inside a > function. > But I haven't looked for them either. > > > Is it there some rule or is it special form specific depending on > > (a) the intended use of the special form > > (b) the mechanics of getting the compiler to use the special form > > First you'd have to find such special forms. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
Hi people! Nice explanation, about the difference of "special form" in Clojure, vs other Lisp. I remember (Queinnec Lisp?): lambda: to make "normal functions" mlambda: to make "macros" (something that produce a form, and then, evaluate that result) flambda: spread, non evaluation of parameters nlambda: non-spread (all arguments in one variable), non evaluation of parameters. Usually, when I wrote a Lisp interpreter, I implement the above "words". AFAIK, Clojure doesn't have any way to build a new special form, except via macros. Why? It was a design decision? motivated by Java compilation? Angel "Java" Lopez http://www.ajlopez.com http://twitter.com/ajlopez On Mon, May 31, 2010 at 11:06 AM, Patrick Stein wrote: > Maybe Clojure uses the term "special form" differently than Common > Lisp does, but here's how to think of "special form" in the Common > Lisp sense. > > A form that is *NOT* a special form like (F A B C D ...) will either > evaluate: > > 1. (SYMBOL-FUNCTION F), then A, B, C, D, ... in order from left-to- > right, OR > 2. A, B, C, D, ... in order from left-to-right then (SYMBOL-FUNCTION > F) > > And, cannot change the lexical environment (add or remove symbols in > the environment). > > It is up to the implementation whether (SYMBOL-FUNCTION F) gets > evaluated first or last, but A, B, C, D, ... get evaluated from let to > right in order before F is invoked. > > Any form that does not ALWAYS obey that is a "special form". > > Examples: > > (+ 3 5 (+ 6 7) ii), the form 3 is evaluated, then 5, then (+ 6 7), > then ii, then all of these are passed to (SYMBOL-FUNCTION +) to > execute. This IS NOT a special form. > > (IF A B C) does not evaluate both B and C. Thus, it IS a special > form. > > The following IS NOT a special form (as long as XX and YY aren't > dynamic variables that we're overriding but rather just local > variables here like it looks) because it always evaluates A and B in > the expected order: > (DEFMACRO WEIRD (A B) > `(LET ((XX ,A)) > (LET ((YY ,B)) > (DO-SOMETHING (+ XX YY) (- XX YY) > > (WEIRD (+ 6 7) ii) > > > The following IS a special form because it does not evaluate A and B > in the expected order: > (DEFMACRO WEIRD-SPECIAL (A B) > `(LET ((YY ,B)) > (LET ((XX ,A)) > (DO-SOMETHING (+ XX YY) (- XX YY) > > (WEIRD-SPECIAL (+ 6 7) ii) > > The following IS also a special form since it doesn't always evaluate > A and B in the expected order: > (DEFMACRO WEIRD-MAY-BE-SPECIAL (SPECIAL A B) > `(IF ,SPECIAL > (LET ((XX ,A)) > (LET ((YY ,B)) >(DO-SOMETHING (+ XX YY) (- XX YY > (LET ((YY ,B)) > (LET ((XX ,A)) >(DO-SOMETHING (+ XX YY) (- XX YY) > > (WEIRD-MAY-BE-SPECIAL (ZEROP (RANDOM 2)) (+ 6 7) ii) > > The term "special form" (at least in Common Lisp) has nothing to do > with whether it is built-in or user-defined. It has to do with > whether or not all of its components are evaluated in the expected > order. > > ttyl, > Patrick > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with > your first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Newbie question about vector performance
On Fri, May 28, 2010 at 12:20 PM, Rubén Béjar wrote: > Hi again, > > I have tried a few more things: > > I have done the same in Java but using an array > of Integers, instead of an array of ints. It just takes > 78 ms. (more than 16, still far less than 4 secs). > > I have also tried with an update function which just returns a > fixed 1. It still takes some 400 ms. to update de > data vector of the CA. This is similar to the time > it is giving me to create a vector of 1's with this function: > (time (vec (repeat 25 1))). > > I was not expecting Clojure vectors so much slower than > Java arrays. Is that comparison so "unfair"? Next thing > I am trying is using Java Vectors in my Java > implementation... > >Rubén > I looked into your code and came up with this: http://gist.github.com/420036 On my machine 500x500 takes about 60-70ms. 2000x2000 takes about ~940ms. Also, Clojure vectors aren't slow: (defn vec-repeat [n x] (loop [n n v (transient [])] (if (zero? n) (persistent! v) (recur (dec n) (conj! v x) (vec-repeat 25 1) Takes 4-7ms (vec-repeat 250 1) Takes 50-60ms Transients aren't an advanced topic, they solve the problem of building up large vectors in a memory/cpu efficient manner. In very tight loops over primitive data: 1. Spending time accessing Clojure data structures can hurt you 2. Spending time creating temporary data structures can hurt you 3. Inline the most called bits. Fast Clojure code that works with arrays need not look ugly (checkout amap and areduce). Also macros can alleviate the tedious typing of type hints. David -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Newbie question about vector performance
On Sun, May 30, 2010 at 3:49 PM, Rubén Béjar wrote: > > is not very precise with that short periods of time) and in Clojure the > 2000x2000 CA > is updated in 98 secs some times and up to 150 s. other times (the 500x500 > was 4 secs), When numbers fluctuate like that I'm pretty sure you're hitting GC. Another reason to use transients if you're going to use vectors to store a lot of data. David -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Hi, On Mon, May 31, 2010 at 07:34:24AM +0200, Sina K. Heshmati wrote: > > (defn make-module > > [] > > (let [state (atom 0) > > say-hello (fn [] (println "Hello")) > > public-op (fn [x y] (+ @state x y))] > > (fn [op] > > (case op > > :hello say-hello > > :public public-op > > Could you elaborate a bit please? Is there a reason why nested defns are > wrong? I'm sorry. I missed this question. def always introduces a global binding. It is unlike schemes define. So invoking make-module twice basically overwrites the first defs with the second ones. Sincerely Meikel -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
Hi, On Mon, May 31, 2010 at 10:21:14AM -0700, Quzanti wrote: > Are you sure that always works? > > I think I am misunderstanding Halloway's Taxonomy of Macro's chapter > > defstruct is written as a macro and Stuart then comments > > "This macro looks so simple that you may be tempted to try to write it > as a function. You won't be able to because def is a special form. You > must generate def at macro time; you cannot make 'dynamic' calls to > def at runtime" It works sometimes. Of course you can redef a Var via function. (defn foo [y] (def x y)) (foo 5) However, you cannot define arbitrary Vars. (defn bar [x y] (def x y)) (bar 'c 5) This does *not* define Var named c. So can't really make 'dynamic' calls to def at runtime. Just as Stuart writes. Sincerely Meikel -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
On May 31, 7:54 pm, Meikel Brandmeyer wrote: > It works sometimes. Of course you can redef a Var via function. > > (defn foo [y] (def x y)) > (foo 5) > > However, you cannot define arbitrary Vars. > > (defn bar [x y] (def x y)) > (bar 'c 5) True, but that's more a question of the interface provided by def. The real problem is that if you want to access the vars defined by that function anywhere else, they need to be defined (if not initialized) before you can compile the code. Meaning you either have to def those vars somewhere else (outside of a function) or make sure the function gets called at least once before any access is mentioned in the code. After that, you can re-define the var in any way you like. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: "special form" vs. "macro"
On May 31, 8:14 pm, Joost wrote: > > True, but that's more a question of the interface provided by def. The > real problem is that if you want to access the vars defined by that > function anywhere else, they need to be defined (if not initialized) > before you can compile the code. Meaning you either have to def those > vars somewhere else (outside of a function) or make sure the function > gets called at least once before any access is mentioned in the code. > > After that, you can re-define the var in any way you like. Update: some testing indicates that that's not actually what happens. What appears to happen is that (def) is always defining when the code is read/compiled, no matter where in the source the def call is actually places (like in a function definition) it's just unbound until you assign a value to it (by "executing" the def form). -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: special forms and let binding
So I don't understand if there any way do it. I'm really curious about it. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Rationals, and their size
On May 31, 12:18 am, alux wrote: > Ah, thank you - I still shy away from looking into Richs sources, but > here it helps: Ratio doesn't have getter for numerator and denominator > - they are just public ;-) Ha! A blindspot due to writing idiomatic java for far too long. > > Being final thats okay of course. > > So. Whether this helps, I dont know too. I still dont have the lever, > but now I have a point to place it at ;-) > > Regards, alux > > On 31 Mai, 04:10, ataggart wrote: > > > > > Ratio doesn't emit the numerator and > > denominator:http://github.com/richhickey/clojure/blob/master/src/jvm/clojure/lang... > > > I'm not sure that would help solve your problem, even if it were > > available. You either need to turn the ratio into a non-ratio (using > > float or double) or use unchecked math functions which are subject to > > truncation (e.g., unchecked-multiply). > > > On May 30, 1:32 pm, alux wrote: > > > > Hello, > > > > I careless used rationals in a function, and, well, it took some > > > minutes to understand why it was slowing down. (I did this formatting > > > by (println (* 1.0 x)) when it started being unreadable - and forgot > > > that). > > > > I still see rationals as very nice, but try to use them carefully now. > > > What I would really like is a possibility to round to a numer of a > > > certain size. Like, to an continued fraction of a certain size. But, > > > there I need access to the length of numerator and denominator. > > > > Now the question - is there any way to access this (or to reach to > > > goal of rounding to a rational), that is easier than using the > > > BigIntegers myself? > > > > Thank you, alux -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: : Google Chrome extension for TryClojure (try-clojure.org)
Missing link https://chrome.google.com/extensions/detail/lhmgejcdhmollecbianopflcfdaennle ;) On 31 май, 16:04, sergey-miryanov wrote: > Hi all, > > I made a little extension for google chrome. It allows to start try- > clojure REPL via clicking on toolbar button. Also it grabs selected > text and evaluates it in REPL. > > Feel free to comment, report bugs and suggestions. > > /Sergey -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
confused about getting started with compojure on google app engine
I was wondering which tutorial I should use to get started with compojure on google app engine. There seem to be a bunch of them but they target old versions or slightly old versions. Which one should I use? -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: (apply interleave [[1 2]])
On May 30, 12:51 am, Eugen Dück wrote:
> How often do you do:
> (+ 5)
> or
> (* 3)
>
> ? But you might have used something like
> (apply + coll)
> or
> (reduce + coll)
>
> and under certain circumstances your coll might have had only one
> element.
This is a good line of reasoning. Let's add an example in quantitative
logic, in which corner cases aren't that obvious at first glance:
user=> (every? pos? #{})
true
Clojure follows the mathematical definition here and concludes that
all members of the empty set are indeed positive :-) This is a useful
behaviour since the programmer probably wanted to keep out non-
positive numbers, and the empty set satisfies this restriction. No
need to check for an empty collection beforehand.
--
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Re: (apply interleave [[1 2]])
On May 31, 10:07 pm, Daniel Werner wrote: > quantitative logic That should have been "quantification logic". -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Rationals, and their size
Yep, know that, been there ;-)) On 31 Mai, 21:39, ataggart wrote: > On May 31, 12:18 am, alux wrote: > > > Ah, thank you - I still shy away from looking into Richs sources, but > > here it helps: Ratio doesn't have getter for numerator and denominator > > - they are just public ;-) > > Ha! A blindspot due to writing idiomatic java for far too long. > > > > > Being final thats okay of course. > > > So. Whether this helps, I dont know too. I still dont have the lever, > > but now I have a point to place it at ;-) > > > Regards, alux > > > On 31 Mai, 04:10, ataggart wrote: > > > > Ratio doesn't emit the numerator and > > > denominator:http://github.com/richhickey/clojure/blob/master/src/jvm/clojure/lang... > > > > I'm not sure that would help solve your problem, even if it were > > > available. You either need to turn the ratio into a non-ratio (using > > > float or double) or use unchecked math functions which are subject to > > > truncation (e.g., unchecked-multiply). > > > > On May 30, 1:32 pm, alux wrote: > > > > > Hello, > > > > > I careless used rationals in a function, and, well, it took some > > > > minutes to understand why it was slowing down. (I did this formatting > > > > by (println (* 1.0 x)) when it started being unreadable - and forgot > > > > that). > > > > > I still see rationals as very nice, but try to use them carefully now. > > > > What I would really like is a possibility to round to a numer of a > > > > certain size. Like, to an continued fraction of a certain size. But, > > > > there I need access to the length of numerator and denominator. > > > > > Now the question - is there any way to access this (or to reach to > > > > goal of rounding to a rational), that is easier than using the > > > > BigIntegers myself? > > > > > Thank you, alux -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: special forms and let binding
Hi Аркадий, I started another thread about the difference between special form and macros today - and got told that it is not possible to overwrite a special form. Regards, alux On 31 Mai, 21:15, "Ark. Rost" wrote: > So I don't understand if there any way do it. I'm really curious about > it. -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Datatype Usage Examples
Hi Meikel, Meikel Brandmeyer wrote: > On Mon, May 31, 2010 at 07:34:24AM +0200, Sina K. Heshmati wrote: > >> > (defn make-module >> > [] >> > (let [state (atom 0) >> > say-hello (fn [] (println "Hello")) >> > public-op (fn [x y] (+ @state x y))] >> > (fn [op] >> > (case op >> > :hello say-hello >> > :public public-op >> >> Could you elaborate a bit please? Is there a reason why nested defns are >> wrong? > > I'm sorry. I missed this question. Thanks for the follow-up. > def always introduces a global binding. It is unlike schemes define. > So invoking make-module twice basically overwrites the first defs > with the second ones. I see now. I used to think of them as defines in Scheme but I started to notice this when I saw them survive closures. Kind regards, SinDoc -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: : Google Chrome extension for TryClojure (try-clojure.org)
try-clojure.org seems to redirect to http://blog.licenser.net/ ?? On Mon, May 31, 2010 at 11:22 AM, sergey-miryanov wrote: > Missing link > https://chrome.google.com/extensions/detail/lhmgejcdhmollecbianopflcfdaennle > ;) > > On 31 май, 16:04, sergey-miryanov wrote: >> Hi all, >> >> I made a little extension for google chrome. It allows to start try- >> clojure REPL via clicking on toolbar button. Also it grabs selected >> text and evaluates it in REPL. >> >> Feel free to comment, report bugs and suggestions. >> >> /Sergey -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: : Google Chrome extension for TryClojure (try-clojure.org)
Also the extension did not seem to work reliably on Chrome 5.0.375.55 beta on Mac OS X. Sometimes clicking the button did not open the popup, sometimes it opened it blank. In most cases it spun up CPU to near 100%. Only once did it open with the REPL on www.try-clojure.org - but it is a cool idea! On Mon, May 31, 2010 at 4:28 PM, Sean Corfield wrote: > try-clojure.org seems to redirect to http://blog.licenser.net/ ?? > > On Mon, May 31, 2010 at 11:22 AM, sergey-miryanov > wrote: >> Missing link >> https://chrome.google.com/extensions/detail/lhmgejcdhmollecbianopflcfdaennle >> ;) >> >> On 31 май, 16:04, sergey-miryanov wrote: >>> Hi all, >>> >>> I made a little extension for google chrome. It allows to start try- >>> clojure REPL via clicking on toolbar button. Also it grabs selected >>> text and evaluates it in REPL. >>> >>> Feel free to comment, report bugs and suggestions. >>> >>> /Sergey -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: : Google Chrome extension for TryClojure (try-clojure.org)
The problem is known and in work, the background is that not all of the DNS entries can be configured directly a request with the DNS provider (which also hosts my blog) is already filed so I can't say how long this takes :). Best regards, Heinz N. Gies aka Licenser On Jun 1, 2010, at 1:28 , Sean Corfield wrote: > try-clojure.org seems to redirect to http://blog.licenser.net/ ?? > > On Mon, May 31, 2010 at 11:22 AM, sergey-miryanov > wrote: >> Missing link >> https://chrome.google.com/extensions/detail/lhmgejcdhmollecbianopflcfdaennle >> ;) >> >> On 31 май, 16:04, sergey-miryanov wrote: >>> Hi all, >>> >>> I made a little extension for google chrome. It allows to start try- >>> clojure REPL via clicking on toolbar button. Also it grabs selected >>> text and evaluates it in REPL. >>> >>> Feel free to comment, report bugs and suggestions. >>> >>> /Sergey > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with your > first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: : Google Chrome extension for TryClojure (try-clojure.org)
Good to know. I'll reinstall it and look forward to using it once DNS has propagated (if that's what's causing the problems with the extension)... On Mon, May 31, 2010 at 4:41 PM, Heinz N. Gies wrote: > The problem is known and in work, the background is that not all of the DNS > entries can be configured directly a request with the DNS provider (which > also hosts my blog) is already filed so I can't say how long this takes :). -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: confused about getting started with compojure on google app engine
Now that would be a fantastic topic for one of Sean Devlin's Full Disclojure videocasts!!! (just a subtle hint from a Full Disclojure fan...;-) ) -Frank. On May 31, 2010, at 12:33 PM, Zitterbewegung wrote: > I was wondering which tutorial I should use to get started with > compojure on google app engine. There seem to be a bunch of them but > they target old versions or slightly old versions. Which one should I > use? > > -- > You received this message because you are subscribed to the Google > Groups "Clojure" group. > To post to this group, send email to clojure@googlegroups.com > Note that posts from new members are moderated - please be patient with your > first post. > To unsubscribe from this group, send email to > clojure+unsubscr...@googlegroups.com > For more options, visit this group at > http://groups.google.com/group/clojure?hl=en -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Reductions bug
Hi! Here it is: (reduce + '()) gives 0 (reductions + '()) gives java.lang.IllegalArgumentException: Don't know how to create ISeq from: java.lang.Integer So reductions not always returns a sequence of intermediate values of the reduction. Thanks! -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
clojure.contrib.repl-utils show
Hi! I created a new project using 'lein new " and then modified the project.clj file to look like this - (defproject datastructures "1.0.0-SNAPSHOT" :dependencies [[org.clojure/clojure "1.2.0-master-SNAPSHOT"] [org.clojure/clojure-contrib "1.2.0-SNAPSHOT"] [ant/ant "1.6.5"] [jline "0.9.94"] [org.apache.maven/maven-ant-tasks "2.0.10"]] :dev-dependencies [[swank-clojure "1.2.1"] [autodoc "0.7.0"]]) I did a 'lein deps' and then a 'lein swank' - I switched over the emacs and did a slime-connect [I am using the emacs-starter-kit with clojure-mode, and swank-clojure installed via ELPA). For some reason, the 'show' function from clojure.contrib.repl-utils does not work. In fact the only completions I get when trying to get to repl-* are clojure.contrib.repl-ln clojure.contrib.repl_ln I noticed that there is now a clojure.repl namespace with a few methods like apropos but no 'show'. Furthermore, when using labrepl (from relevance) and doing a script/ swank 'show' works just fine. Both lib directories contain the same jars labrepl/lib => clojure-1.2.0-master-20100528.120302-79.jar clojure-contrib-1.2.0-20100528.120551-119.jar new_project/lib => clojure-1.2.0-master-20100528.120302-79.jar clojure-contrib-1.2.0-20100528.120551-119.jar Is there something I am missing? Thank you! -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
I've been using Swing. But, one thing to consider is that many (most?) big applications use extension libraries such as JIDE (https://jide- oss.dev.java.net/), SwingX (https://swingx.dev.java.net/) or Flamingo (https://flamingo.dev.java.net/). They contain extra widgets that have their own extra APIs of course. So while abstracting "the JDK Swing" (or any other toolkit) away would be a huge thing, it would be somewhat lacking regardless. Do you think the DSL you described would be easily extensible to work with that kind of extension libraries? If not, maybe that could be one reason to use a some other toolkit (more complete than basic Swing) as a base for the DSL. Best Regards, Joonas On May 27, 6:18 pm, Luke VanderHart wrote: > My side project is a fairly complex GUI application written in > Clojure. Recently, I've become irritated with using Java interop for > everything. It's not that Clojure doesn't have nice java interop - it > does. It's just that when interacting with a GUI framework, which is a > large part of my app, I have to be back in mutable object-oriented > land, worrying about class hierarchies, mutable state, locks, etc. > Yucky. > > So, with a perhaps dangerous lack of sanity and without any guarantee > of success, I've decided to try my hand at writing an idiomatic > Clojure GUI library. If I have success (which I doubt) I will of > course make it available as open source. > > I intend for it to be mostly declarative, with a nice DSL for defining > GUI elements. Each component will also implement map, and use one of > Clojure's reference types as an interface for inspecting / updating > its state. I may also implement some aspects of Functional Reactive > Programming wherever it's convenient to do so. > > What you all must help me decide is what GUI framework to use as the > underpinnings of it. It's genuinely hard to decide. I have at least > some experience with all of them, so I have no strong preference, but > I'd like to get your input. I did consider trying to make it abstract > enough that you could plug in *any* of them under the hood, but > there's enough differences between the frameworks that that would get > very ugly very fast. > > Possibilities are: > > AWT > Pros: native widgets, bundled with Java, low-level > Cons: few widgets, considered somewhat obselete > > Swing > Pros: bundled with Java, good widget selection > Cons: non-native widgets > > SWT > Pros: native widgets, widely used > Cons: requires platform-specific libs > > QT Jambi > Pros: native widgets, huge widget selection, highly-regarded framework > Cons: requires platform-specific libs, writing custom widgets is > hairy, momentum and support seem to be lagging since Nokia dropped > official support. > > Remember, the actual API won't matter - that will be completely > abstracted away. So try to focus on the framework's look and feel. > Also let me know if I've missed any of the framework's key > characteristics. > > Thanks! > > -Luke -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Reductions bug
Hi, this is already filed: http://www.assembla.com/spaces/clojure/tickets/362-incorrect-result-of-reductions-for-empty-input-sequences Sincerely Meikel -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: clojure.contrib.repl-utils show
Hi, On Jun 1, 4:16 am, looselytyped wrote: > For some reason, the 'show' function from clojure.contrib.repl-utils > does not work. In fact the only completions I get when trying to get > to repl-* are > > clojure.contrib.repl-ln > clojure.contrib.repl_ln Did you (require 'clojure.contrib.repl-ln)? Maybe labrepl does that for you. Sincerely Meikel -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Reductions bug
Looks like a bug in reductions? The lazy-seq macro expects something
the implements ISeq, but the result of (+) is 0. Not sure if this is
the right fix, but it works.
(defn reductions
"Returns a lazy seq of the intermediate values of the reduction (as
per reduce) of coll by f, starting with init."
{:added "1.2"}
([f coll]
(lazy-seq
(if-let [s (seq coll)]
(reductions f (first s) (rest s))
[(f)])))
([f init coll]
(cons init
(lazy-seq
(when-let [s (seq coll)]
(reductions f (f init (first s)) (rest s)))
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Re: Which GUI toolkit would you like to see wrapped in an idiomatic Clojure library?
to achieve something a bit "thicker" that could insulate the user from Java classes completely. The user wouldn't even have to know Swing or handle JObjects or worry about the event thread... In other words, it wouldn't be a wrapper API for Swing, but a Clojure GUI api that, coincidentally, is /backed/ by Swing. Sounds like a good idea. Swing is great but to be useful needs some higher level layer anyway. I'm doing something like you probaly have in mind for JRuby. A high level GUI framework that supports (in theory) different frameworks. Right now it works with swing and SWT. Maybe we could share some ideas ? Regards Roger -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
Re: Understanding sequence abstraction
@Richard
>> 1. In case coll is a LazySeq why does (seq coll) realize its first
>> element? I thought seq just did a type conversion and all of list,
>> vector .. etc implemented Seqable or something.
> Because seq is defined as returning nil for an empty sequence. The
> only way to find that out for a lazy sequence is to realize the first
> element.
I'm not sure if that answers why seq should realize the first
element. Even by what you say, only if I wanted to find if my LazySeq
was nil should I realize its first element.
My understanding of seq is - restricting some Collection type
abstraction to the Sequence abstraction (but maybe my thinking is
wrong). When I say (seq coll) I don't mean - 1) convert it into a
sequence abstraction + 2) go and find out if the coll is empty by
realizing its first element.
For example suppose I've produce a lazy sequence none of whose
elements are realized yet. Then I need to call an API which takes a
sequence as input. I just want to give the sequence abstraction of my
LazySeq by calling (seq coll), but that realizes the first element
(which takes 10 mins say), even if the API were not to use my LazySeq
at all (based on its needs) ! How to solve this - i.e. how do I not
waste 10 mins if not needed?
In fact I'm not even sure why I would need to realize the first
element (completely?) (which takes 10 mins) to find out if the LazySeq
is not empty ? Can you please explain this further?
>> 2. Why is there no other way to determine an empty coll except (not
>> (seq coll)).
>user=> (empty? [])
>true
1:291 user=> (source empty?)
(defn empty?
"Returns true if coll has no items - same as (not (seq coll)).
Please use the idiom (seq x) rather than (not (empty? x))"
{:added "1.0"}
[coll] (not (seq coll)))
nil
Which brings it back to my original question.
Thanks
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