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Hashes now use integers instead of fixnums, it seems?

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Suzanne Soy 2021-04-04 19:51:27 +01:00
parent 864d8b110e
commit 7a01fad928
2 changed files with 14 additions and 20 deletions
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22
phc-adt-lib/phc-adt/node-low-level.hl.rkt
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@ -104,17 +104,11 @@ same if the @tc[database] and @tc[index] is the same for both nodes.
(eq? (raw-node-database a) (raw-node-database b))
(equal? (raw-node-index a) (raw-node-index b))))
(λ (a r)
(fxxor (eq-hash-code (raw-node-database a))
(let ([i (r (raw-node-index a))])
(if (fixnum? i)
i
(error "index too big")))))
(bitwise-xor (eq-hash-code (raw-node-database a))
(r (raw-node-index a))))
(λ (a r)
(fxxor (eq-hash-code (raw-node-database a))
(let ([i (r (raw-node-index a))])
(if (fixnum? i)
i
(error "index too big"))))))]
(bitwise-xor (eq-hash-code (raw-node-database a))
(r (raw-node-index a)))))]
The following function can then be used to test if two nodes are the same, based
on the contents of their @tc[raw] field:
@ -227,7 +221,7 @@ them with a special marker.
@chunk[<node-hash>
(: node-hash (∀ (fieldᵢ/τ …)
(→ (node-id fieldᵢ/τ … Any Any) (→ Any Fixnum) Fixnum)))
(→ (node-id fieldᵢ/τ … Any Any) (→ Any Integer) Integer)))
(define (node-hash nd racket-recur-hash)
(if (eq? (raw-node-database ((struct-accessor node-id raw) nd))
'unique-copy)
@ -281,9 +275,9 @@ To combine hash codes, we simply compute their @elem[#:style 'tt]{xor}. Later
versions of this library may use more sophisticated mechanisms.
@chunk[<combine-hash-codes>
(: combine-hash-codes (→ Fixnum * Fixnum))
(define (combine-hash-codes . fixnums)
(apply fxxor fixnums))]
(: combine-hash-codes (→ Integer * Integer))
(define (combine-hash-codes . hashes)
(apply bitwise-xor hashes))]
@subsection{Caching node equality}

12
phc-adt-lib/phc-adt/tagged-structure-low-level.hl.rkt
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@ -235,13 +235,13 @@ nodes have the same shape, but cannot by themselves create logical cycles.
…
#t))
(λ (a rec-hash)
(fxxor (rec-hash 'id)
(rec-hash (force ((struct-accessor pid fieldᵢ) a)))
…))
(bitwise-xor (rec-hash 'id)
(rec-hash (force ((struct-accessor pid fieldᵢ) a)))
…))
(λ (a rec-hash)
(fxxor (rec-hash 'id)
(rec-hash (force ((struct-accessor pid fieldᵢ) a)))
…))))]
(bitwise-xor (rec-hash 'id)
(rec-hash (force ((struct-accessor pid fieldᵢ) a)))
…))))]
@section{Pre-declaring structs}