Idiom for gathering pairs from a list?

[Robert L.]

Zach Beane wrote:

> "bradb" <brad.beveri...@gmail.com> writes:
> > I'm using CL-PPCRE, and some functions return lists of start and end
> > matches, so a return might be
> > (0 2 4 7 10 15), three matches.
> > Right now I loop over the matches like
> > (loop :for match :on (all-matches scanner text :start start) :by
> > #'cddr
> > :do (let ((start (first match))
> > (end (second match)))
> > (subseq text start end))
>
> > Is there a nicer way to gather the pairs than that?
>
> LOOP destructures. Try this:
>
> (loop for (start end) on (all-matches ...) by #'cddr do ...)

(define text "abcdefghijklmnopq")

(g.each
(compose displayln (curry apply substring text))
(gen-slices 2 '(0 2 4 7 10 15)))

===>
ab
efg
klmno

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