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  • Re: Lis(t|p) comprehensions

    From B. Pym@Nobody447095@here-nor-there.org to comp.lang.lisp,comp.lang.scheme on Sat Jul 19 04:18:14 2025
    From Newsgroup: comp.lang.lisp

    Frank Buss wrote:

    joswig@corporate-world.lisp.de wrote:

    For combinations of this kind of stuff I really prefer the functional approach:
    CL-USER 5 > (remove-if-not 'oddp '(1 2 3))
    (1 3)

    I know it is possible, but I'm not sure aboout how to write the following with a functional approach:

    (loop for i from 1 to 10 collect (loop for j from 1 to i collect j))
    ((1) (1 2) (1 2 3) (1 2 3 4) (1 2 3 4 5) (1 2 3 4 5 6) (1 2 3 4 5 6 7) (1 2
    3 4 5 6 7 8) (1 2 3 4 5 6 7 8 9) (1 2 3 4 5 6 7 8 9 10))

    Is "map" functional enough?

    Gauche Scheme:

    (map (cut iota <> 1) (iota 10 1))

    ===>
    ((1) (1 2) (1 2 3) (1 2 3 4) (1 2 3 4 5) (1 2 3 4 5 6)
    (1 2 3 4 5 6 7) (1 2 3 4 5 6 7 8) (1 2 3 4 5 6 7 8 9)
    (1 2 3 4 5 6 7 8 9 10))
    --
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