Talk:cons

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Not fundamental[edit]

Could somebody check those definitions? They don't look right and they don't seem to work. 84.191.247.10 (talk) 23:26, 19 August 2008 (UTC)[reply]

They look fine to me. Tried them out under guile and they worked as expected. (Named them mycons, mycar, and mycdr because I didn’t want to clobber the built-in functions.) --Malirath (talk) 17:40, 31 March 2009 (UTC)[reply]
I'm not clear on how you could think they aren't right or how they might "seem" not to work, unless you simply don't understand the notation or the subject matter -- in which case you should just say so. cons returns a closure that applies a function to the two values. car invokes the closure with a function that returns the first value, and cdr invokes the closure with a function that returns the second value -- it couldn't be much simpler or more straightforward. -- 98.108.225.155 (talk) 07:25, 19 November 2010 (UTC)[reply]
I'm new to scheme, but just trying the cons definition in common music (a scheme) did not do the same thing as cons. specifically:
(define (mycons x y)
(lambda (m) (m x y)))
and then (mycons 3 5) returns #<lambda (m)>. How is this returned function supposed to be called?
this is not the same as (cons 3 5), which returns the dotted pair (3 . 5). At any rate some clarification or reference would be helpful to those new to thinking functionally such as myself — Preceding unsigned comment added by Sebfumaster (talk • contribs) 05:42, 16 September 2014 (UTC)[reply]

snoc[edit]

I'm tempted to remove the recent addition of Cons#Snoc. Cons is a primitve operation, but snoc is not. (snoc a b) is a cute name for what Lisp would refer to as (with args reversed) (append b (list a)) or (nconc b (cons a NIL)). It is not a common operation and seems to have little merit. Append is a clearer name, and real code might use a trailing pointer. If snoc needs to be explained, then it can be explained there instead of redirecting here. Glrx (talk) 00:46, 16 January 2014 (UTC)[reply]


Why does that mean you should remove it? This article is not bloated. Crasshopper (talk) 11:52, 20 April 2015 (UTC)[reply]
Anon here, Am working on a research language, and the need for a snoc-like function came up because it would eliminate a copy. I don't think I should have had to come to the Talk section to see the idea discussed. — Preceding unsigned comment added by 173.19.237.184 (talk) 23:24, 14 May 2015 (UTC)[reply]
snoc is a common term in functional programing and it should have a subsection in this article. In general it would be good to write the article such that it abstracts away from Lisp, since Nil/Cons representation of lists is a functional programing concept not restricted to Lisp. --Tobias (Talk) 13:24, 14 May 2019 (UTC)[reply]

"ordered pairs of simplex data"[edit]

Which of the many definitions does simplex (disambiguation) mean in this article? Crasshopper (talk) 11:47, 20 April 2015 (UTC)[reply]

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