Ooops - my apologies (attempted correction below)
Here is a horribly contrived example (sorry, that's all I can come up
withht now rig) using recur across different arities of the same function,
together with trampoline.
(defn is-odd?
([n]
(cond (< n 0) true
(even? n) #(is-odd?
I don't think you're missing anything James. It does not look like this
example uses trampoline with the intended effect.
On Wednesday, April 20, 2016 at 2:45:05 PM UTC-4, James Elliott wrote:
>
> Does trampoline really help in this case? I don’t see where we are ever
> returning a new
Does trampoline really help in this case? I don’t see where we are ever
returning a new function for trampoline to call, avoiding a new stack
frame. It seems to me no different than simply calling the other arities
directly in this example. What am I missing?
On Wednesday, April 20, 2016 at
You can prevent stack consumption by using trampoline for tail-recursive
calls to a different arity, and recur for same arity, something like:
(defn find-comment-in-line
([s] (when (pos? (count s))
(if-let [cs (seq (comment-s? s))]
;; yes, a comment symbol found,
;;
You can prevent stack consumption by using trampoline for tail-recursive
calls to a different arity, and recur for same arity, something like:
(defn find-comment-in-line
([s] (when (pos? (count s))
(if-let [cs (seq (comment-s? s))]
;; yes, a comment symbol found,
;;
But recur does not do that. Recur does not call a function at all. It is
the opposite of calling a function, it says “I want to loop, without the
overhead of calling a function and creating a stack frame.” Recur is even
used outside of functions entirely; it is how you iterate using the (loop
Thank you. That the point. If "recur" binds to fn, why it can not know the
binding point as the function method based on the number of arguments
passed to it? I mean it is clear that Clojure can't do that, but I can see
no reason why it could or should not if we choose to implement such
And the reason for this is to be able to simulate tail-call optimization
even though the Java VM doesn’t natively support that; recur can allow you
to express things in a style that looks recursive, but does not suffer from
stack space limitations that actual recursive calls do. If you actually
Each arity defined for a particular Clojure function is actually a separate
"method" under the hood for that particular functional instance. `recur` in
Clojure should be thought of as more like a primitive looping construct
than a recursive call to some named function.
The documentation for
Hello
I am just a beginner Clojure programmer and I am unhappy with the way recur
behaves in Clojure
I have implemented kata from
here https://github.com/alvarogarcia7/kata-formulation-find-comments/pull/3
What it does: it outputs 'comments' (sequences starting with "#" or "//")
and ignores
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