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comp / comp.lang.lisp / re: Generating code which compiles to a jmphash

Subject: re: Generating code which compiles to a jmphash
From: B. Pym
Newsgroups: comp.lang.lisp
Organization: A noiseless patient Spider
Date: Thu, 18 Jul 2024 16:10 UTC

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From: Nobody447095@here-nor-there.org (B. Pym)
Newsgroups: comp.lang.lisp
Subject: re: Generating code which compiles to a jmphash
Date: Thu, 18 Jul 2024 16:10:44 -0000 (UTC)
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fvmarcoline wrote:

> (defconstant dirs '(up down left right))
>
> (defun all-moves ()
>
> (loop for dir in dirs
> append
> (loop for i from 0 to 4
> collect (list i dir))))
>
> (defun move-to-int (move)
> (+ (first move) (* 5 (position (second move) dirs))))
>
> > (nth 12 (all-moves))
> => (2 left)
> > (map 'list 'move-to-int (all-moves))
> => (0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19)

Gauche Scheme

(define dirs '(up down left right))
(define dir-table (map cons dirs '(0 5 10 15)))

(define (all-moves)
(append-map
(^(dir) (map (^i (list i dir)) (lrange 0 5)))
dirs))

(define (move-to-int move)
(+ (car move) (assv-ref dir-table (cadr move))))

(~ (all-moves) 12)
===>
(2 left)

(map move-to-int (all-moves))
===>
(0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19)

Subject	Author
re: Generating code which compiles to a jmphash	B. Pym