[lnkForumImage]
TotalShareware - Download Free Software
Confronta i prezzi di migliaia di prodotti.
Asp Forum
 Home | Login | Register | Search 


 

Forums >

comp.lang.lisp

Re: (funcall #'or my-list

William James

12/28/2015 10:39:00 PM

Rob St. Amant wrote:

> I've lately found a use for a function that calls a predicate on each
> element of a list and returns all non-null results. (I bring this up
> here because it has a SOME-like flavor).
>
> (defun all-such-that (predicate list &key key)
> "Return non-nil PREDICATE results for elements in LIST."
> (loop for elt in list
> as value = (if key
> (funcall predicate (funcall key elt))
> (funcall predicate elt))
> when value
> collect value))

MatzLisp (Ruby):

def filter_map array
result = []
array.each{|elt| val=yield(elt); result << val if val}
result
end

filter_map([2,3,4,5]){|n| n.odd? && n*n}
==>[9, 25]

--
Amazon bans book. After nearly a month on the site, all traces of the book and
its 80 reviews have been removed.
http://jamesfetzer.blogspot.com/2015/11/debunking-sandy-hook-debunk...
https://www.youtube.com/watch?v=E...