Ok. I got back to this, now running Cora's gist. It gives me a different place to explore these issues. More soon. Jack
On Tue, Jul 20, 2021 at 5:31 PM Jack Park <jackp...@topicquests.org> wrote: > Hi Cora, > > I got dragged away but plan to study your contribution, which I deeply > appreciate. > > My project plans to be a very simple clojure re-implementation of an > inference engine I wrote in Forth more than 20 years ago, a kind of list > processor in which you have an interface which advertises a simple > "eval"-like method, applicable to structures as well as atoms. Thus, > conjunctive and disjunctive lists, plus not, all of which can be populated > with combinations of those and atoms, tiny computational objects which do > stuff within the same interface. Atoms can ask questions at the UI, do > computations on databases, and so forth. > > I benchmarked that against a more traditional symbolic (frame-based) > inference I had written to control autoclaves for curing polymer resins - a > contract for the military which ended up helping to fix fighter jets which > were grounded because of bird impacts penetrating composite leading edges > and crashing - we were able to cure improved leading edges; the new code > executed more than 10 times faster than the old symbolic code. That was > then (Forth), this is now (Java/Clojure). I've done it in Java. Now it's > time to use that as a learning exercise. > > Many thanks > Jack > > On Mon, Jul 19, 2021 at 6:04 PM Cora Sutton <c...@sutton.me> wrote: > >> Hello again, Jack. I'm not sure what your code looked like before or >> looks like now but I think maybe a different way of helping you out with >> this is in order. Here's some code that does what I think you're going for >> and runs: >> >> https://gist.github.com/corasaurus-hex/1c86b545644b734310a15d984f61ad99 >> >> Have a look, play with it a bit, change around value and see what breaks. >> Hope that's helpful! >> >> On Mon, Jul 19, 2021 at 5:55 PM Jack Park <jackp...@topicquests.org> >> wrote: >> >>> Did. That suggestion was made earlier. Did not change anything. >>> >>> Here's a test which ran just fine >>> (def x (evaluate_and (list true true))) >>> (println "A" x) >>> (def y (evaluate_and (list true false))) >>> (println "B" y) >>> >>> But, the moment I attempt to make a list with two functions in it, the >>> code breaks and returns - without any errors - not a boolean, but the >>> structure I passed it. >>> >>> >>> On Mon, Jul 19, 2021 at 3:43 PM Cora Sutton <c...@sutton.me> wrote: >>> >>>> Those are functions that call booleans as functions. Try this: >>>> >>>> (defn simple-true [] true) >>>> >>>> On Mon, Jul 19, 2021 at 5:41 PM Jack Park <jackp...@topicquests.org> >>>> wrote: >>>> >>>>> Great points! >>>>> They are filled with functions which look like this >>>>> >>>>> (defn simple_true [] (true)) >>>>> >>>>> They are not booleans but functions which return a boolean. >>>>> Here is a list of two of those as produced by the code: >>>>> >>>>> (#object[ie4clj.Tests$simple_false 0x3a4621bd >>>>> ie4clj.Tests$simple_false@3a4621bd] >>>>> #object[ie4clj.Tests$simple_false 0x3a4621bd >>>>> ie4clj.Tests$simple_false@3a4621bd]) >>>>> >>>>> Or maybe I missed something. >>>>> >>>>> On Mon, Jul 19, 2021 at 3:33 PM Cora Sutton <c...@sutton.me> wrote: >>>>> >>>>>> Your members list needs to be filled with things that can be called >>>>>> as functions, since that's what that code snippet does, and booleans >>>>>> definitely cannot be called as functions. That's what the error means, >>>>>> there's a boolean in your list and it's trying to cast it to an IFn (a >>>>>> Clojure function interface) when it is called as (member). >>>>>> >>>>>> Can you show the lists you construct? Are they full of functions that >>>>>> take no arguments? Do you want the lists to be able to contain booleans >>>>>> too? >>>>>> >>>>>> On Mon, Jul 19, 2021 at 2:57 PM Jack Park <jackp...@topicquests.org> >>>>>> wrote: >>>>>> >>>>>>> Cora >>>>>>> >>>>>>> (every? (fn [member] (member)) members) >>>>>>> works fine on [constantly true & false >>>>>>> but fails with >>>>>>> java.lang.Boolean cannot be cast to clojure.lang.IFn >>>>>>> on the lists I construct. >>>>>>> >>>>>>> In truth, I thought all the code was working, but that turned out ot >>>>>>> be an artifact of the test I designed. When I changed the test >>>>>>> conditions, >>>>>>> evaluate_and failed. >>>>>>> >>>>>>> >>>>>>> On Sun, Jul 18, 2021 at 5:00 PM Cora Sutton <c...@sutton.me> wrote: >>>>>>> >>>>>>>> Hello again Jack, >>>>>>>> >>>>>>>> On Sun, Jul 18, 2021 at 6:21 PM Jack Park <jackp...@topicquests.org> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> (every? eval members) does not appear to work on a list of >>>>>>>>> functions designed to evaluate to a boolean. >>>>>>>>> >>>>>>>> >>>>>>>> If members is a list of functions then you would do: >>>>>>>> >>>>>>>> (every? (fn [member] (member)) members) >>>>>>>> >>>>>>>> Showing it work here: >>>>>>>> >>>>>>>> (every? (fn [member] (member)) [(constantly true) (constantly >>>>>>>> true)]) >>>>>>>> ;; => true >>>>>>>> (every? (fn [member] (member)) [(constantly true) (constantly >>>>>>>> false)]) >>>>>>>> ;; => false >>>>>>>> >>>>>>>> >>>>>>>>> That code is used in a function evaluateAnd >>>>>>>>> >>>>>>>>> Two simple tests >>>>>>>>> (evaluateAnd [true true] --> true >>>>>>>>> (evaluateAnd [true false] --> nil (why not "false" as the every? >>>>>>>>> examples show?) >>>>>>>>> >>>>>>>> >>>>>>>> In Clojure things are either "truthy" or "falsey", and the only >>>>>>>> "false" values are false and nil so returning nil is usually fine. >>>>>>>> Everything else is "truthy". I wouldn't worry about it returning nil >>>>>>>> since >>>>>>>> other things were broken anyways. >>>>>>>> >>>>>>>> https://clojure.org/guides/learn/flow#_truth >>>>>>>> >>>>>>>> >>>>>>>>> The specific code for building the list of functions is this >>>>>>>>> >>>>>>>>> (def x (atom [])) >>>>>>>>> (let [result (list (ref SimpleTrue) (ref SimpleFalse))] >>>>>>>>> (println "BAL1" result ) >>>>>>>>> (reset! x result) >>>>>>>>> ) >>>>>>>>> (println "BAL2" @x ) >>>>>>>>> >>>>>>>>> (@x) <<<< returns the atom's value >>>>>>>>> >>>>>>>>> And the final println is this >>>>>>>>> >>>>>>>>> BAL2 (#object[clojure.lang.Ref 0x335b5620 {:status :ready, :val >>>>>>>>> #object[ie4clj.Tests$SimpleTrue 0x6eb2384f >>>>>>>>> ie4clj.Tests$SimpleTrue@6eb2384f]}] >>>>>>>>> #object[clojure.lang.Ref 0x3c9c0d96 {:status :ready, :val >>>>>>>>> #object[ie4clj.Tests$SimpleFalse 0x31dadd46 >>>>>>>>> ie4clj.Tests$SimpleFalse@31dadd46]}]) >>>>>>>>> >>>>>>>>> evaluateAnd never saw the result, with this error message >>>>>>>>> >>>>>>>>> clojure.lang.PersistentList cannot be cast to clojure.lang.IFn >>>>>>>>> >>>>>>>> >>>>>>>> Refs are the wrong thing to use here. In fact I'd stay away from >>>>>>>> atoms and refs unless you have multiple threads that need to mutate the >>>>>>>> same values. They're just confusing things now, I think. >>>>>>>> >>>>>>>> >>>>>>>>> >>>>>>>>> The test which fails is this >>>>>>>>> >>>>>>>>> (def result (evaluateAnd (buildAndList) )) <<< fails here >>>>>>>>> (println "bar" result) >>>>>>>>> (result) >>>>>>>>> >>>>>>>>> The googleverse seems to agree that there are extra parens around >>>>>>>>> the value. Google isn't giving me an obvious way to take that value >>>>>>>>> outside >>>>>>>>> of its surrounding parens (bal2 above). >>>>>>>>> Still looking, and hoping that solves the problem. >>>>>>>>> Maybe there's a way to go back to buildAndList and not return the >>>>>>>>> value with parens. >>>>>>>>> >>>>>>>> >>>>>>>> I think a key thing to explain is that in Clojure generally you're >>>>>>>> not making new types of collections. There's this famous-ish saying >>>>>>>> that >>>>>>>> Clojure holds to pretty well: >>>>>>>> >>>>>>>> "It is better to have 100 functions operate on one data structure >>>>>>>> than 10 functions on 10 data structures." >>>>>>>> - Alan Perlis >>>>>>>> >>>>>>>> Most functions in the Clojure world operate on a handful of basic >>>>>>>> data types and structures. This makes it really easy to chain and >>>>>>>> combine >>>>>>>> functions to slice and dice data since you don't need to convert >>>>>>>> between >>>>>>>> types. >>>>>>>> >>>>>>>> I don't think I've ever made a special collection type in Clojure, >>>>>>>> it's not all that common. So I'd suggest that while you're at this >>>>>>>> point in >>>>>>>> your journey you try to stick to the built-in Clojure collection types >>>>>>>> and >>>>>>>> use the built-in functions to operate on them. >>>>>>>> >>>>>>>> To give you a little direction, instead of a Person object you >>>>>>>> could make a hashmap like {:first-name "Jack" :last-name "Park"} and >>>>>>>> pass that around. And then you can make a function that operates on >>>>>>>> that. >>>>>>>> >>>>>>>> (defn full-name >>>>>>>> [person] >>>>>>>> (str (get person :first-name) " " (get person :last-name))) >>>>>>>> >>>>>>>> And then you could expand that to maybe {:first-name "Jack" >>>>>>>> :last-name "Park" :people-talked-to-on-mailing-list ["Cora Sutton"]} >>>>>>>> and >>>>>>>> then operate on a collection of people like: >>>>>>>> >>>>>>>> (defn people-talked-to-on-mailing-list >>>>>>>> [person all-people] >>>>>>>> (let [people-to-find (set (get person >>>>>>>> :people-talked-to-on-mailing-list))] >>>>>>>> (filter (fn [p] >>>>>>>> (people-to-find (full-name p)) >>>>>>>> all-people)) >>>>>>>> >>>>>>>> (people-talked-to-on-mailing-list jack all-people) >>>>>>>> ;; => {:first-name "Cora" :last-name "Sutton" >>>>>>>> :people-talked-to-on-mailing-list ["Jack Park"]} >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>>> On Sun, Jul 18, 2021 at 11:23 AM Cora Sutton <c...@sutton.me> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Hi Jack! >>>>>>>>>> >>>>>>>>>> I could be wrong but I think this could just be: (every? eval >>>>>>>>>> members) >>>>>>>>>> >>>>>>>>>> I see a few things here that seem strange to me so I wanted to >>>>>>>>>> share a few points that might be helpful (or might not, let me know >>>>>>>>>> either >>>>>>>>>> way) for future code. >>>>>>>>>> >>>>>>>>>> * So typically you don't want to def or defn within another >>>>>>>>>> function call since that will define a new value at the top level. >>>>>>>>>> >>>>>>>>>> (defn foo [] >>>>>>>>>> (def bar 1) >>>>>>>>>> (println (inc bar)) >>>>>>>>>> >>>>>>>>>> (foo) >>>>>>>>>> ;; ^^ calling foo will define bar at the top level >>>>>>>>>> >>>>>>>>>> bar >>>>>>>>>> ;; => 1 >>>>>>>>>> ;; whoops, didn't mean to have that at the top level like that >>>>>>>>>> ;; imagine if two different threads called that in parallel >>>>>>>>>> ::grimace:: >>>>>>>>>> >>>>>>>>>> Instead, you usually want to use the let function: >>>>>>>>>> https://clojuredocs.org/clojure.core/let >>>>>>>>>> >>>>>>>>>> So in your code you might use this something like: >>>>>>>>>> >>>>>>>>>> (let [result (atom true)] >>>>>>>>>> ....) >>>>>>>>>> >>>>>>>>>> The error you're seeing is from the (defn result ...) in your >>>>>>>>>> code, you're missing the argument vector [] after result -- so >>>>>>>>>> it would look like (defn result [] (atom true)) -- but you >>>>>>>>>> really don't want to defn like that, I think. >>>>>>>>>> >>>>>>>>>> * To update an atom's value you don't want to assign like that, >>>>>>>>>> you want to use swap! https://clojuredocs.org/clojure.core/swap! >>>>>>>>>> >>>>>>>>>> (swap! f >>>>>>>>>> (fn [cur-val new-val] (and cur-val new-val)) >>>>>>>>>> (eval member)) >>>>>>>>>> >>>>>>>>>> * You probably don't want to use an atom here. Atoms are usually >>>>>>>>>> for data that you intend to have multiple threads accessing. In this >>>>>>>>>> case >>>>>>>>>> it's just a value that changes during a single thread's execution >>>>>>>>>> here. >>>>>>>>>> >>>>>>>>>> How else could you solve this if not for the very convenient >>>>>>>>>> every? function? There are a bunch of ways! Here are a few, with >>>>>>>>>> things written out pretty explicitly so they're more clear. >>>>>>>>>> >>>>>>>>>> loop/recur: >>>>>>>>>> >>>>>>>>>> (loop [result true >>>>>>>>>> remaining-members members] >>>>>>>>>> (let [member (first remaining-members) >>>>>>>>>> remaining-members (rest members) >>>>>>>>>> new-result (eval member)] >>>>>>>>>> (if new-result >>>>>>>>>> (recur true remaining-members) >>>>>>>>>> false))) >>>>>>>>>> >>>>>>>>>> reduce v1: >>>>>>>>>> >>>>>>>>>> (reduce (fn [result member] >>>>>>>>>> (and result >>>>>>>>>> (eval member))) >>>>>>>>>> true >>>>>>>>>> members) >>>>>>>>>> >>>>>>>>>> reduce v2.0, that will now stop iterating once one of the members >>>>>>>>>> evals to false: >>>>>>>>>> >>>>>>>>>> (reduce (fn [_ member] >>>>>>>>>> (or (eval member) >>>>>>>>>> (reduced false))) >>>>>>>>>> true >>>>>>>>>> members) >>>>>>>>>> >>>>>>>>>> My point with sharing these is that in clojure usually the best >>>>>>>>>> way to solve these problems is to pass new values to the next >>>>>>>>>> iteration >>>>>>>>>> while accumulating a result instead of changing a variable on each >>>>>>>>>> iteration. Or to use one of these sweet built-in functions. >>>>>>>>>> >>>>>>>>>> Does that make sense? >>>>>>>>>> >>>>>>>>>> * I thiiiiiiink you might not mean eval but I'm interested in >>>>>>>>>> what kind of problem you're solving! :) >>>>>>>>>> >>>>>>>>>> Hope that helps! >>>>>>>>>> Cora >>>>>>>>>> >>>>>>>>>> On Sun, Jul 18, 2021 at 12:41 PM Jack Park < >>>>>>>>>> jackp...@topicquests.org> wrote: >>>>>>>>>> >>>>>>>>>>> I have a class which treats a sequence as a conjunctive list of >>>>>>>>>>> objects which, when evaluated, return a boolean. It is an attempt >>>>>>>>>>> to use >>>>>>>>>>> doseq to walk along that list, evaluating each entry, and anding >>>>>>>>>>> that >>>>>>>>>>> result with boolean atom. It fails. A sketch of the code is this - >>>>>>>>>>> taken >>>>>>>>>>> from the error message: >>>>>>>>>>> >>>>>>>>>>> inside (defn AndList... >>>>>>>>>>> >>>>>>>>>>> (reify >>>>>>>>>>> ie4clj.api.Inferrable >>>>>>>>>>> (defn evalMembers >>>>>>>>>>> [members] >>>>>>>>>>> (defn result (atom true)) >>>>>>>>>>> (doseq [x members] >>>>>>>>>>> (result = (and result (eval x)))) >>>>>>>>>>> (println (clojure.core/deref result)) >>>>>>>>>>> (result))) - *failed: vector? at: [:fn-tail :arity-1 >>>>>>>>>>> :params] spec: :clojure.core.specs.alpha/param-list* >>>>>>>>>>> >>>>>>>>>>> It could be that my Java background is clouding my use of >>>>>>>>>>> clojure. Any comments will be appreciated. >>>>>>>>>>> >>>>>>>>>>> Thanks >>>>>>>>>>> Jack >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> 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 unsubscribe from this group and stop receiving emails from >>>>>>>>>>> it, send an email to clojure+unsubscr...@googlegroups.com. >>>>>>>>>>> To view this discussion on the web visit >>>>>>>>>>> https://groups.google.com/d/msgid/clojure/f67cfcd0-8e1e-4780-bc00-f6993979e7afn%40googlegroups.com >>>>>>>>>>> <https://groups.google.com/d/msgid/clojure/f67cfcd0-8e1e-4780-bc00-f6993979e7afn%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>>>>>> . >>>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> 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 unsubscribe from this group and stop receiving emails from it, >>>>>>>>>> send an email to clojure+unsubscr...@googlegroups.com. >>>>>>>>>> To view this discussion on the web visit >>>>>>>>>> https://groups.google.com/d/msgid/clojure/CAMZDCY3BWybiXzgoYaKK958z%2BWqTKf0o_5p9fq-huwutco9onw%40mail.gmail.com >>>>>>>>>> <https://groups.google.com/d/msgid/clojure/CAMZDCY3BWybiXzgoYaKK958z%2BWqTKf0o_5p9fq-huwutco9onw%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>>>> . >>>>>>>>>> >>>>>>>>> -- >>>>>>>>> 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 unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to clojure+unsubscr...@googlegroups.com. >>>>>>>>> To view this discussion on the web visit >>>>>>>>> https://groups.google.com/d/msgid/clojure/CAH6s0fwv-rKrWnXji_r4scaX9_jtAi1CRUWGLLNRj7iZtme4UA%40mail.gmail.com >>>>>>>>> <https://groups.google.com/d/msgid/clojure/CAH6s0fwv-rKrWnXji_r4scaX9_jtAi1CRUWGLLNRj7iZtme4UA%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>>> . >>>>>>>>> >>>>>>>> >>>>>>>> On Sun, Jul 18, 2021 at 6:21 PM Jack Park <jackp...@topicquests.org> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> (every? eval members) does not appear to work on a list of >>>>>>>>> functions designed to evaluate to a boolean. >>>>>>>>> >>>>>>>>> That code is used in a function evaluateAnd >>>>>>>>> >>>>>>>>> Two simple tests >>>>>>>>> (evaluateAnd [true true] --> true >>>>>>>>> (evaluateAnd [true false] --> nil (why not "false" as the every? >>>>>>>>> examples show?) >>>>>>>>> >>>>>>>>> The specific code for building the list of functions is this >>>>>>>>> >>>>>>>>> (def x (atom [])) >>>>>>>>> (let [result (list (ref SimpleTrue) (ref SimpleFalse))] >>>>>>>>> (println "BAL1" result ) >>>>>>>>> (reset! x result) >>>>>>>>> ) >>>>>>>>> (println "BAL2" @x ) >>>>>>>>> >>>>>>>>> (@x) <<<< returns the atom's value >>>>>>>>> >>>>>>>>> And the final println is this >>>>>>>>> >>>>>>>>> BAL2 (#object[clojure.lang.Ref 0x335b5620 {:status :ready, :val >>>>>>>>> #object[ie4clj.Tests$SimpleTrue 0x6eb2384f >>>>>>>>> ie4clj.Tests$SimpleTrue@6eb2384f]}] >>>>>>>>> #object[clojure.lang.Ref 0x3c9c0d96 {:status :ready, :val >>>>>>>>> #object[ie4clj.Tests$SimpleFalse 0x31dadd46 >>>>>>>>> ie4clj.Tests$SimpleFalse@31dadd46]}]) >>>>>>>>> >>>>>>>>> evaluateAnd never saw the result, with this error message >>>>>>>>> >>>>>>>>> clojure.lang.PersistentList cannot be cast to clojure.lang.IFn >>>>>>>>> >>>>>>>>> The test which fails is this >>>>>>>>> >>>>>>>>> (def result (evaluateAnd (buildAndList) )) <<< fails here >>>>>>>>> (println "bar" result) >>>>>>>>> (result) >>>>>>>>> >>>>>>>>> The googleverse seems to agree that there are extra parens around >>>>>>>>> the value. Google isn't giving me an obvious way to take that value >>>>>>>>> outside >>>>>>>>> of its surrounding parens (bal2 above). >>>>>>>>> Still looking, and hoping that solves the problem. >>>>>>>>> Maybe there's a way to go back to buildAndList and not return the >>>>>>>>> value with parens. >>>>>>>>> >>>>>>>>> On Sun, Jul 18, 2021 at 11:23 AM Cora Sutton <c...@sutton.me> >>>>>>>>> wrote: >>>>>>>>> >>>>>>>>>> Hi Jack! >>>>>>>>>> >>>>>>>>>> I could be wrong but I think this could just be: (every? eval >>>>>>>>>> members) >>>>>>>>>> >>>>>>>>>> I see a few things here that seem strange to me so I wanted to >>>>>>>>>> share a few points that might be helpful (or might not, let me know >>>>>>>>>> either >>>>>>>>>> way) for future code. >>>>>>>>>> >>>>>>>>>> * So typically you don't want to def or defn within another >>>>>>>>>> function call since that will define a new value at the top level. >>>>>>>>>> >>>>>>>>>> (defn foo [] >>>>>>>>>> (def bar 1) >>>>>>>>>> (println (inc bar)) >>>>>>>>>> >>>>>>>>>> (foo) >>>>>>>>>> ;; ^^ calling foo will define bar at the top level >>>>>>>>>> >>>>>>>>>> bar >>>>>>>>>> ;; => 1 >>>>>>>>>> ;; whoops, didn't mean to have that at the top level like that >>>>>>>>>> ;; imagine if two different threads called that in parallel >>>>>>>>>> ::grimace:: >>>>>>>>>> >>>>>>>>>> Instead, you usually want to use the let function: >>>>>>>>>> https://clojuredocs.org/clojure.core/let >>>>>>>>>> >>>>>>>>>> So in your code you might use this something like: >>>>>>>>>> >>>>>>>>>> (let [result (atom true)] >>>>>>>>>> ....) >>>>>>>>>> >>>>>>>>>> The error you're seeing is from the (defn result ...) in your >>>>>>>>>> code, you're missing the argument vector [] after result -- so >>>>>>>>>> it would look like (defn result [] (atom true)) -- but you >>>>>>>>>> really don't want to defn like that, I think. >>>>>>>>>> >>>>>>>>>> * To update an atom's value you don't want to assign like that, >>>>>>>>>> you want to use swap! https://clojuredocs.org/clojure.core/swap! >>>>>>>>>> >>>>>>>>>> (swap! f >>>>>>>>>> (fn [cur-val new-val] (and cur-val new-val)) >>>>>>>>>> (eval member)) >>>>>>>>>> >>>>>>>>>> * You probably don't want to use an atom here. Atoms are usually >>>>>>>>>> for data that you intend to have multiple threads accessing. In this >>>>>>>>>> case >>>>>>>>>> it's just a value that changes during a single thread's execution >>>>>>>>>> here. >>>>>>>>>> >>>>>>>>>> How else could you solve this if not for the very convenient >>>>>>>>>> every? function? There are a bunch of ways! Here are a few, with >>>>>>>>>> things written out pretty explicitly so they're more clear. >>>>>>>>>> >>>>>>>>>> loop/recur: >>>>>>>>>> >>>>>>>>>> (loop [result true >>>>>>>>>> remaining-members members] >>>>>>>>>> (let [member (first remaining-members) >>>>>>>>>> remaining-members (rest members) >>>>>>>>>> new-result (eval member)] >>>>>>>>>> (if new-result >>>>>>>>>> (recur true remaining-members) >>>>>>>>>> false))) >>>>>>>>>> >>>>>>>>>> reduce v1: >>>>>>>>>> >>>>>>>>>> (reduce (fn [result member] >>>>>>>>>> (and result >>>>>>>>>> (eval member))) >>>>>>>>>> true >>>>>>>>>> members) >>>>>>>>>> >>>>>>>>>> reduce v2.0, that will now stop iterating once one of the members >>>>>>>>>> evals to false: >>>>>>>>>> >>>>>>>>>> (reduce (fn [_ member] >>>>>>>>>> (or (eval member) >>>>>>>>>> (reduced false))) >>>>>>>>>> true >>>>>>>>>> members) >>>>>>>>>> >>>>>>>>>> My point with sharing these is that in clojure usually the best >>>>>>>>>> way to solve these problems is to pass new values to the next >>>>>>>>>> iteration >>>>>>>>>> while accumulating a result instead of changing a variable on each >>>>>>>>>> iteration. Or to use one of these sweet built-in functions. >>>>>>>>>> >>>>>>>>>> Does that make sense? >>>>>>>>>> >>>>>>>>>> * I thiiiiiiink you might not mean eval but I'm interested in >>>>>>>>>> what kind of problem you're solving! :) >>>>>>>>>> >>>>>>>>>> Hope that helps! >>>>>>>>>> Cora >>>>>>>>>> >>>>>>>>>> On Sun, Jul 18, 2021 at 12:41 PM Jack Park < >>>>>>>>>> jackp...@topicquests.org> wrote: >>>>>>>>>> >>>>>>>>>>> I have a class which treats a sequence as a conjunctive list of >>>>>>>>>>> objects which, when evaluated, return a boolean. It is an attempt >>>>>>>>>>> to use >>>>>>>>>>> doseq to walk along that list, evaluating each entry, and anding >>>>>>>>>>> that >>>>>>>>>>> result with boolean atom. It fails. A sketch of the code is this - >>>>>>>>>>> taken >>>>>>>>>>> from the error message: >>>>>>>>>>> >>>>>>>>>>> inside (defn AndList... >>>>>>>>>>> >>>>>>>>>>> (reify >>>>>>>>>>> ie4clj.api.Inferrable >>>>>>>>>>> (defn evalMembers >>>>>>>>>>> [members] >>>>>>>>>>> (defn result (atom true)) >>>>>>>>>>> (doseq [x members] >>>>>>>>>>> (result = (and result (eval x)))) >>>>>>>>>>> (println (clojure.core/deref result)) >>>>>>>>>>> (result))) - *failed: vector? at: [:fn-tail :arity-1 >>>>>>>>>>> :params] spec: :clojure.core.specs.alpha/param-list* >>>>>>>>>>> >>>>>>>>>>> It could be that my Java background is clouding my use of >>>>>>>>>>> clojure. Any comments will be appreciated. >>>>>>>>>>> >>>>>>>>>>> Thanks >>>>>>>>>>> Jack >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> 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 unsubscribe from this group and stop receiving emails from >>>>>>>>>>> it, send an email to clojure+unsubscr...@googlegroups.com. >>>>>>>>>>> To view this discussion on the web visit >>>>>>>>>>> https://groups.google.com/d/msgid/clojure/f67cfcd0-8e1e-4780-bc00-f6993979e7afn%40googlegroups.com >>>>>>>>>>> <https://groups.google.com/d/msgid/clojure/f67cfcd0-8e1e-4780-bc00-f6993979e7afn%40googlegroups.com?utm_medium=email&utm_source=footer> >>>>>>>>>>> . >>>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> 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 unsubscribe from this group and stop receiving emails from it, >>>>>>>>>> send an email to clojure+unsubscr...@googlegroups.com. >>>>>>>>>> To view this discussion on the web visit >>>>>>>>>> https://groups.google.com/d/msgid/clojure/CAMZDCY3BWybiXzgoYaKK958z%2BWqTKf0o_5p9fq-huwutco9onw%40mail.gmail.com >>>>>>>>>> <https://groups.google.com/d/msgid/clojure/CAMZDCY3BWybiXzgoYaKK958z%2BWqTKf0o_5p9fq-huwutco9onw%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>>>> . >>>>>>>>>> >>>>>>>>> -- >>>>>>>>> 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 unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to clojure+unsubscr...@googlegroups.com. >>>>>>>>> To view this discussion on the web visit >>>>>>>>> https://groups.google.com/d/msgid/clojure/CAH6s0fwv-rKrWnXji_r4scaX9_jtAi1CRUWGLLNRj7iZtme4UA%40mail.gmail.com >>>>>>>>> <https://groups.google.com/d/msgid/clojure/CAH6s0fwv-rKrWnXji_r4scaX9_jtAi1CRUWGLLNRj7iZtme4UA%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>>> . >>>>>>>>> >>>>>>>> -- >>>>>>>> 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 unsubscribe from this group and stop receiving emails from it, >>>>>>>> send an email to clojure+unsubscr...@googlegroups.com. >>>>>>>> >>>>>>> To view this discussion on the web visit >>>>>>>> https://groups.google.com/d/msgid/clojure/CAMZDCY1wvo_N32dKV1g-9cZAmTbZUO5bRAXDGkdHm-7_VD_-Rg%40mail.gmail.com >>>>>>>> <https://groups.google.com/d/msgid/clojure/CAMZDCY1wvo_N32dKV1g-9cZAmTbZUO5bRAXDGkdHm-7_VD_-Rg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>>> . >>>>>>>> >>>>>>> -- >>>>>>> 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 unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to clojure+unsubscr...@googlegroups.com. >>>>>>> To view this discussion on the web visit >>>>>>> https://groups.google.com/d/msgid/clojure/CAH6s0fyc%2BctV%2B1OgzWRYLsWevL97ouVkS1FGf0uGFtTcznRjUg%40mail.gmail.com >>>>>>> <https://groups.google.com/d/msgid/clojure/CAH6s0fyc%2BctV%2B1OgzWRYLsWevL97ouVkS1FGf0uGFtTcznRjUg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>>> . >>>>>>> >>>>>> -- >>>>>> 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 unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to clojure+unsubscr...@googlegroups.com. >>>>>> >>>>> To view this discussion on the web visit >>>>>> https://groups.google.com/d/msgid/clojure/CAMZDCY0qvUUrTmQtfcUocwWbr50juXzoZt%3DSmPr%3D0o%3DgRXoM2A%40mail.gmail.com >>>>>> <https://groups.google.com/d/msgid/clojure/CAMZDCY0qvUUrTmQtfcUocwWbr50juXzoZt%3DSmPr%3D0o%3DgRXoM2A%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>>> . >>>>>> >>>>> -- >>>>> 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 unsubscribe from this group and stop receiving emails from it, send >>>>> an email to clojure+unsubscr...@googlegroups.com. >>>>> To view this discussion on the web visit >>>>> https://groups.google.com/d/msgid/clojure/CAH6s0fxJXPC8Y%3DY_UEAsAyMek4FZwo%2BP9bVahzrVKQLKGd%3D3Lg%40mail.gmail.com >>>>> <https://groups.google.com/d/msgid/clojure/CAH6s0fxJXPC8Y%3DY_UEAsAyMek4FZwo%2BP9bVahzrVKQLKGd%3D3Lg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>>> . >>>>> >>>> -- >>>> 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 unsubscribe from this group and stop receiving emails from it, send >>>> an email to clojure+unsubscr...@googlegroups.com. >>>> To view this discussion on the web visit >>>> https://groups.google.com/d/msgid/clojure/CAMZDCY3BKpWAu6%3D%2BEC6o3PSGg7CXETgyZymOBKLnhEJYG7UVdQ%40mail.gmail.com >>>> <https://groups.google.com/d/msgid/clojure/CAMZDCY3BKpWAu6%3D%2BEC6o3PSGg7CXETgyZymOBKLnhEJYG7UVdQ%40mail.gmail.com?utm_medium=email&utm_source=footer> >>>> . >>>> >>> -- >>> 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 unsubscribe from this group and stop receiving emails from it, send >>> an email to clojure+unsubscr...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/clojure/CAH6s0fz-Y9c9asSx85jrvrHvjLdX2qgLgjt8yPdxpHu_4X_vGg%40mail.gmail.com >>> <https://groups.google.com/d/msgid/clojure/CAH6s0fz-Y9c9asSx85jrvrHvjLdX2qgLgjt8yPdxpHu_4X_vGg%40mail.gmail.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- >> 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 unsubscribe from this group and stop receiving emails from it, send an >> email to clojure+unsubscr...@googlegroups.com. >> To view this discussion on the web visit >> https://groups.google.com/d/msgid/clojure/CAMZDCY2fYJoAVPxngBiib41-2T%3DWsKL3QNQhw6%3DZe%2BpSKuPQKg%40mail.gmail.com >> <https://groups.google.com/d/msgid/clojure/CAMZDCY2fYJoAVPxngBiib41-2T%3DWsKL3QNQhw6%3DZe%2BpSKuPQKg%40mail.gmail.com?utm_medium=email&utm_source=footer> >> . >> > -- 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 unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/clojure/CAH6s0fz05OratKeQTGy9Ss0J4-8A%3D_TVOPS41fUuTeQVuWaxBQ%40mail.gmail.com.
