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cs: adapt (unused) Patricia trie implementation for negative hash codes

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The hashing protocol has been adjusted since the Patricia trie
implementation so that the result can be negative. Force it to
avoid breaking an assumption in the Patricia-trie implementation
(even though this implementation is not currently used).
This commit is contained in:
Matthew Flatt 2021-04-05 11:39:17 -06:00
parent 4d23c6da5a
commit e58a3d9dda
1 changed files with 6 additions and 3 deletions
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9
racket/src/cs/rumble/patricia.ss
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@ -258,10 +258,13 @@
[(eq? et 'eqv) (eqv? k1 k2)]
[else (key-equal? k1 k2)]))
(define-syntax-rule (to-fxpositive e)
(fxand e (most-positive-fixnum)))
(define-syntax-rule (hash-code et k)
(cond [(eq? et 'eq) (eq-hash-code k)]
[(eq? et 'eqv) (eqv-hash-code k)]
[else (key-equal-hash-code k)]))
(cond [(eq? et 'eq) (to-fxpositive (eq-hash-code k))]
[(eq? et 'eqv) (to-fxpositive (eqv-hash-code k))]
[else (to-fxpositive (key-equal-hash-code k))]))
;; iteration
(define (intmap-iterate-first t)