Subject: RE: bug#4136: 23.1; delete-pair

From: Drew Adams <[email-masked]>
Date: Mon, 16 Nov 2020 13:37:09 -0800 (PST)

> The closest function that I found is:
> 
>   (cl-plusp NUMBER)
>   Return t if NUMBER is positive.
> 
> but I'm not sure why it would be better than using just (> number 0).

It's there to emulate a Common Lisp predicate, `plusp'.

Why does Common Lisp have `plusp'?  Presumably for
use with higher-order functions, to not have to use
a lambda form etc.

(mapcar #'plusp '(4 -3.1 0 42))
(mapcar (lambda (x) (> x 0)) '(4 -3.1 0 42))