On Thu, Nov 19, 2009 at 05:51:22AM -0500, John Harrop wrote:
>On Thu, Nov 19, 2009 at 4:31 AM, Lauri Pesonen wrote:
>
>> (clojure.walk/macroexpand-all '(cond (even? 2) :foo (odd? 2) :bar :else
>> :baz))
>> (if (even? 2) :foo (if (odd? 2) :bar (if :else :baz nil)))
>
>Eeeuw. Perhaps the cond macro
On Thu, Nov 19, 2009 at 4:31 AM, Lauri Pesonen wrote:
> (clojure.walk/macroexpand-all '(cond (even? 2) :foo (odd? 2) :bar :else
> :baz))
> (if (even? 2) :foo (if (odd? 2) :bar (if :else :baz nil)))
Eeeuw. Perhaps the cond macro should check if the last condition is
self-evaluating and, if it is
2009/11/18 Jacek Laskowski :
>
> user=> (macroexpand '(-> v (assoc i (v j)) (assoc j (v i
> (assoc (clojure.core/-> v (assoc i (v j))) j (v i))
>
> How to expand the macro in the subform above?
You can use clojure.walk/macroexpand-all:
(clojure.walk/macroexpand-all '(cond (even? 2) :foo (odd?
On Sat, Nov 14, 2009 at 11:59 PM, Meikel Brandmeyer wrote:
> And there is always macroexpand(-1)...
>
> user=> (macroexpand-1 '(-> foo (bar baz)))
> (bar foo baz)
I'm glad you've pointed it out as I've recently been asking myself how
to expand a macro entirely (including subforms)? I'd prefer kn
Hi,
Am 13.11.2009 um 17:29 schrieb Lauri Pesonen:
I hope this helps. I don't think I did a particularly good job in
explaining how the macro works...
And there is always macroexpand(-1)...
user=> (macroexpand-1 '(-> foo (bar baz)))
(bar foo baz)
Sincerely
Meikel
smime.p7s
Description:
Hi Mark,
2009/11/13 Mark Tomko :
>
> I notice you used the '->' macro. Perhaps I'm a little dense, but I
> haven't found the documentation for it to be terribly helpful. Do you
> have simple, succinct explanation for what it does?
The -> macro calls the given forms with the return value of prev
Indeed it does. I still think the array implementation of a heap is
probably worth using, in spite of its use of indexes, but rather than
use a generalized swap implementation to percolate elements up and
down the tree, I'll stick with a vector implementation and keep it all
hidden beneath the imp
Yeah, and this code has the side effect of working on maps
user=>(swap [:a :b :c :d] 0 2)
[:c :b :a :d]
user=>(swap {:a "1" :b "2" :c "3" :d "4"} :a :c)
{:a "3", :b "2", :c "1", :d "4"}
Hmmm... is this worth keeping? Maybe use the name switch instead, to
avoid confusion with swap! (the atom op
It's a pet peeve of mine but, please, try hard not to use indices :-)
(or if you need indices pick a better suited data structure)
The code you try to write is hard to write because you are going
against the grain.
If you try to write swap for vectors (which support efficient random
lookup and ass
Let's try this again:
(defn swap [coll i j]
(if (= i j) coll
(let [li (min i j) ui (max i j)]
(let [[pre-li post-li] (split-at li coll)]
(let [[post-li-pre-ui post-li-post-ui]
(split-at (- ui 1 li) (rest post-li))]
(concat
pre-li
Oh, I posted too soon. My implementation has a bug.
On Nov 12, 9:56 pm, Mark Tomko wrote:
> I came up with a way to do it, but I'm sure there's a simpler way.
> Here's what I have:
>
> (defn swap [coll i j]
> (let [li (min i j) ui (max i j)]
> (let [[pre-li post-li] (split-at li coll)]
>
I came up with a way to do it, but I'm sure there's a simpler way.
Here's what I have:
(defn swap [coll i j]
(let [li (min i j) ui (max i j)]
(let [[pre-li post-li] (split-at li coll)]
(let [[post-li-pre-ui post-li-post-ui] (split-at (- ui 1) (rest
post-li))]
(concat
p
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