Created
October 14, 2015 17:21
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Macro assoc
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| (import (scheme base) (scheme write)) | |
| (define-syntax assocm | |
| (syntax-rules () | |
| ((_ key (alist ...)) | |
| (letrec-syntax ((foo (syntax-rules (key) | |
| ((_ (key . e) res (... ...)) '(key . e)) | |
| ((_ (a . d) res (... ...)) (foo res (... ...)))))) | |
| (foo alist ...))))) | |
| (display (assocm c ((a . b) (b . d) (c . d) (d . d)))) (newline) |
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