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4713e957ca
Author | SHA1 | Date |
---|---|---|
Tony Garnock-Jones | 4713e957ca | |
Tony Garnock-Jones | 3bfc9b910a | |
Tony Garnock-Jones | 26bd5c7638 | |
Tony Garnock-Jones | f6a8b84d81 | |
Tony Garnock-Jones | a5dc977d73 | |
Tony Garnock-Jones | 0b0020153e | |
Tony Garnock-Jones | 10803adcd2 |
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@ -0,0 +1,52 @@
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#lang racket/base
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;; Poor-man's memoization.
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(provide memoize1)
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(define sentinel (cons #f #f))
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(define (memoize1 f)
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(define results (make-weak-hash))
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(lambda (arg)
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(hash-ref results arg (lambda ()
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(define val (f arg))
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(hash-set! results arg val)
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val))))
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(module+ test
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(require rackunit)
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(define call-counter 0)
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(define (raw x)
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(set! call-counter (+ call-counter 1))
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(gensym 'raw-result))
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(define cooked (memoize1 raw))
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;; These tests will *likely* pass, but if garbage collection strikes
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;; at an inopportune moment, they may fail.
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(collect-garbage)
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(define v (cons 1 2))
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(check-equal? call-counter 0)
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(check-eq? (cooked v) (cooked v))
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(check-equal? call-counter 1)
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(set! v (cons 1 2))
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(check-equal? call-counter 1)
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(check-equal? (cooked v) (cooked v))
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(check-equal? call-counter 1)
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(set! v (cons 1 2))
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(collect-garbage)
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(collect-garbage)
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(collect-garbage)
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(check-equal? call-counter 1)
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(check-equal? (cooked v) (cooked v))
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(check-equal? call-counter 2))
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@ -55,6 +55,8 @@
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(require (only-in racket/port call-with-output-string with-output-to-string))
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(require (only-in racket/class object?))
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(require "canonicalize.rkt")
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(require "sorted-map.rkt")
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(require data/order)
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(require rackunit)
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@ -102,13 +104,13 @@
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;; - #f, indicating no further matches possible
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;; - (success Any), representing a successful match (if the end of
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;; the input has been reached)
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;; - (HashTable (U Sigma Wildcard) Matcher), {TODO}
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;; TODO::: reimplement to use (ordinary-state (Option Matcher) (HashTable Sigma Matcher)), {TODO}
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;; - (SortedMap (U Sigma Wildcard) Matcher), {TODO}
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;; TODO::: reimplement to use (ordinary-state (Option Matcher) (SortedMap Sigma Matcher)), {TODO}
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;; - (wildcard-sequence Matcher), {TODO}
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;; If, in a hashtable matcher, a wild key is present, it is intended
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;; If, in a sorted-map matcher, a wild key is present, it is intended
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;; to catch all and ONLY those keys not otherwise present in the
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;; table.
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;; INVARIANT: if a key is present in a hashtable, then the
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;; INVARIANT: if a key is present in a sorted-map, then the
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;; corresponding value MUST NOT be equal to the wildcard
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;; continuation, bearing in mind that
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;; - if the wildcard is absent, it is implicitly #f;
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@ -127,7 +129,7 @@
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;; - ILM, signifying the transition into the cdr position of a pair
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;; - EOS, signifying the notional close-paren at the end of a compound.
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;; - any other value, representing itself.
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;; N.B. hash-tables cannot be Sigmas at present.
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;; N.B. sorted-maps cannot be Sigmas at present.
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(define-singleton-struct SOL start-of-list "<")
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(define-singleton-struct SOV start-of-vector "<vector")
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(define-singleton-struct ILM improper-list-marker "|")
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@ -162,8 +164,8 @@
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(or (eq? x #f)
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(success? x)
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(wildcard-sequence? x)
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(and (hash? x)
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(for/and ([v (in-hash-values x)])
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(and (sorted-map? x)
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(for/and ([v (sorted-map-values x)])
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(matcher? v)))))
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;; -> Matcher
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@ -192,14 +194,33 @@
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(define (rsuccess v)
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(and v (canonicalize (success v))))
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;; Order for sigmas
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(define (sigma-order a b)
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(define sta? (struct-type? a))
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(define stb? (struct-type? b))
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(cond
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[(and sta? stb?) (datum-order (struct-type-name a) (struct-type-name b))]
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[sta? '<]
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[stb? '>]
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[else (datum-order a b)]))
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;; (SortedMap (U Sigma Wildcard) Matcher)
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;; The empty branch-matcher
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(define empty-smap (sorted-map-empty sigma-order))
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;; (U Sigma Wildcard) Matcher -> Matcher
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;; Prepends e to r, if r is non-empty.
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(define (rseq e r)
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(if (matcher-empty? r) r (canonicalize (hash e r))))
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(if (matcher-empty? r)
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r
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(sorted-map-insert empty-smap e r)))
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;; [ (U Sigma Wildcard) Matcher ] ... -> Matcher
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(define (rseq-multi . ers)
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(canonicalize (apply hash ers)))
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(let walk ((ers ers))
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(match ers
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[(list* e r rest) (sorted-map-insert (walk rest) e r)]
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[(list) empty-smap])))
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;; Matcher -> Matcher
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;; Prepends the wildcard pseudo-Sigma to r, if r is non-empty.
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@ -221,27 +242,27 @@
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[_ #f]))
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;; Matcher (U Sigma Wildcard) Matcher -> Matcher
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;; r must be a hashtable matcher. Retrieves the continuation after
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;; r must be a sorted-map matcher. Retrieves the continuation after
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;; accepting key. If key is absent, returns wild-edge-value, modified
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;; depending on key.
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(define (rlookup r key wild-edge-value)
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(hash-ref r key (lambda ()
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(cond
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[(key-open? key) (rwildseq wild-edge-value)]
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[(key-close? key) (runwildseq wild-edge-value)]
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[else wild-edge-value]))))
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(sorted-map-get r key (lambda ()
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(cond
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[(key-open? key) (rwildseq wild-edge-value)]
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[(key-close? key) (runwildseq wild-edge-value)]
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[else wild-edge-value]))))
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;; (Option (HashTable (U Sigma Wildcard) Matcher)) Sigma Matcher -> Matcher
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;; (Option (SortedMap (U Sigma Wildcard) Matcher)) Sigma Matcher -> Matcher
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;; Updates (installs or removes) a continuation in the Matcher r. r
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;; must be either #f or a hashtable matcher. key MUST NOT be ?.
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;; must be either #f or a sorted-map matcher. key MUST NOT be ?.
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;; Preserves invariant that a key is never added if its continuation
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;; is the same as the wildcard's continuation (which is implicitly #f
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;; if absent, of course).
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(define (rupdate r0 key k)
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(when (eq? key ?) (error 'rupdate "Internal error: supplied wildcard as key"))
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(define r (or r0 (hash)))
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(empty-hash-guard
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(let ((old-wild (hash-ref r ? (lambda () #f))))
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(define r (or r0 empty-smap))
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(empty-smap-guard
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(let ((old-wild (sorted-map-get r ? (lambda () #f))))
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(if (cond [(key-open? key)
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(if (wildcard-sequence? k)
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(requal? (wildcard-sequence-matcher k) old-wild)
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@ -252,14 +273,14 @@
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(matcher-empty? k))]
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[else
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(requal? k old-wild)])
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(hash-remove r key)
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(hash-set r key k)))))
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(sorted-map-delete r key)
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(sorted-map-insert r key k)))))
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;; Hash -> Matcher
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;; SortedMap -> Matcher
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;; If the argument is empty, returns the canonical empty matcher;
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;; otherwise, (canonicalizes and) returns the argument.
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(define (empty-hash-guard h)
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(and (positive? (hash-count h)) (canonicalize h)))
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;; otherwise, returns the argument.
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(define (empty-smap-guard h)
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(and (positive? (sorted-map-size h)) h))
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;; Pattern compilation
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@ -285,13 +306,13 @@
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[(cons p1 p2) (rseq SOL (walk p1 (walk-pair-chain p2 acc)))]
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[(? vector? v) (rseq SOV (vector-foldr walk (rseq EOS acc) v))]
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[(embedded-matcher m) (matcher-append m (lambda (_mv) acc))]
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;; TODO: consider options for treating sorted-maps as compounds
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;; rather than (useless) atoms
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[(? sorted-map?) (error 'pattern->matcher "Cannot match on sorted-maps at present")]
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[(? non-object-struct?)
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(rseq (struct->struct-type p)
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(walk-pair-chain (cdr (vector->list (struct->vector p)))
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acc))]
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;; TODO: consider options for treating hash tables as compounds
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;; rather than (useless) atoms
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[(? hash?) (error 'pattern->matcher "Cannot match on hash tables at present")]
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[other (rseq other acc)]))
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(walk-pair-chain ps0 (rsuccess v)))
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@ -371,7 +392,8 @@
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[((wildcard-sequence r1) r2) (f (expand-wildseq r1) r2)]
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[(r1 (wildcard-sequence r2)) (f r1 (expand-wildseq r2))]
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[((success v1) (success v2)) (rsuccess (vf v1 v2))]
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[((? hash? h1) (? hash? h2)) (fold-over-keys h1 h2 f (left-base h1) (right-base h2))]))
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[((? sorted-map? h1) (? sorted-map? h2))
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(fold-over-keys h1 h2 f (left-base h1) (right-base h2))]))
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(define (fold-over-keys h1 h2 f left-base right-base)
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(define w1 (rlookup h1 ? #f))
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@ -380,35 +402,48 @@
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(cond
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[(and w1 w2)
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(for/fold [(acc (rwild (f w1 w2)))]
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[(key (set-remove (set-union (hash-keys h1) (hash-keys h2)) ?))]
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[(key (set-remove (set-union (sorted-map-keys h1) (sorted-map-keys h2)) ?))]
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(rupdate acc key (f (rlookup h1 key w1) (rlookup h2 key w2))))]
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[w1
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(for/fold [(acc left-base)] [(key (in-hash-keys h2))]
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(for/fold [(acc left-base)] [(key (sorted-map-keys h2))]
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(rupdate acc key (f (rlookup h1 key w1) (rlookup h2 key w2))))]
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[w2
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(for/fold [(acc right-base)] [(key (in-hash-keys h1))]
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(for/fold [(acc right-base)] [(key (sorted-map-keys h1))]
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(rupdate acc key (f (rlookup h1 key w1) (rlookup h2 key w2))))]
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[(< (hash-count h1) (hash-count h2))
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(for/fold [(acc right-base)] [(key (in-hash-keys h1))]
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[(< (sorted-map-size h1) (sorted-map-size h2))
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(for/fold [(acc right-base)] [(key (sorted-map-keys h1))]
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(rupdate acc key (f (rlookup h1 key w1) (rlookup h2 key w2))))]
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[else
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(for/fold [(acc left-base)] [(key (in-hash-keys h2))]
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(for/fold [(acc left-base)] [(key (sorted-map-keys h2))]
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(rupdate acc key (f (rlookup h1 key w1) (rlookup h2 key w2))))])))
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;; Matcher -> Matcher
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;; When a matcher contains only entries for (EOS -> m') and (★ ->
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;; (wildcard-sequence m')), it is equivalent to (wildcard-sequence m')
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;; itself. Also, if it's just (★ -> (wildcard-sequence m')), that's
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;; equivalent to (wildcard-sequence m'). This is nearly the inverse of
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;; expand-wildseq.
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(define (collapse-wildcard-sequences m)
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(match m
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[(hash-table ((== ?) (and w (wildcard-sequence wk)))
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((? key-close?) k))
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(if (requal? k wk) w m)]
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[(hash-table ((== ?) (and w (wildcard-sequence wk))))
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w]
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[_ m]))
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;; itself. This is the inverse of expand-wildseq.
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;;
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;; In addition, we rewrite (★ -> (wildcard-sequence m')) to
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;; (wildcard-sequence m'), since matcher-match-value will fall back to
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;; ★ if EOS is missing, and rlookup adjusts appropriately.
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(define collapse-wildcard-sequences
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(let ((expanded-keys1 (set ? EOS))
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(expanded-keys2 (set ?)))
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(lambda (m)
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(if (sorted-map? m)
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(let ((keys (sorted-map-keys m)))
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(cond
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[(equal? keys expanded-keys1)
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(define w (sorted-map-get m ?))
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(define k (sorted-map-get m EOS))
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(if (and (wildcard-sequence? w) (requal? k (wildcard-sequence-matcher w)))
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w
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m)]
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[(equal? keys expanded-keys2)
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(define w (sorted-map-get m ?))
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(if (wildcard-sequence? w) w m)]
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[else
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m]))
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m))))
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;; Sigma -> Boolean
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;; True iff k represents the start of a compound datum.
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@ -425,8 +460,7 @@
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;; Matcher -> Matcher
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;; Unrolls the implicit recursion in a wildcard-sequence.
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(define (expand-wildseq r)
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(canonicalize (hash ? (rwildseq r)
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EOS r)))
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(sorted-map-insert (sorted-map-insert empty-smap ? (rwildseq r)) EOS r))
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;; Matching single keys into a multimap
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@ -458,8 +492,8 @@
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(null? stack))
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result
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failure-result)]
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[(? hash?)
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(define (get key) (hash-ref r key (lambda () #f)))
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[(? sorted-map?)
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(define (get key) (sorted-map-get r key (lambda () #f)))
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(match vs
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['()
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(match stack
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@ -498,17 +532,17 @@
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[((wildcard-sequence r1) r2) (walk (expand-wildseq r1) r2 acc)]
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[(r1 (wildcard-sequence r2)) (walk r1 (expand-wildseq r2) acc)]
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[((success v1) (success v2)) ((matcher-match-matcher-successes) v1 v2 acc)]
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[((? hash? h1) (? hash? h2))
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[((? sorted-map? h1) (? sorted-map? h2))
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(define w1 (rlookup h1 ? #f))
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(define w2 (rlookup h2 ? #f))
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(define r (walk w1 w2 acc))
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(for/fold [(r r)]
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[(key (cond
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[(and w1 w2) (set-remove (set-union (hash-keys h1) (hash-keys h2)) ?)]
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[w1 (hash-keys h2)]
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[w2 (hash-keys h1)]
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[(< (hash-count h1) (hash-count h2)) (hash-keys h1)]
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[else (hash-keys h2)]))]
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[(and w1 w2) (set-remove (set-union (sorted-map-keys h1) (sorted-map-keys h2)) ?)]
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[w1 (sorted-map-keys h2)]
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[w2 (sorted-map-keys h1)]
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[(< (sorted-map-size h1) (sorted-map-size h2)) (sorted-map-keys h1)]
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[else (sorted-map-keys h2)]))]
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(walk (rlookup h1 key w1) (rlookup h2 key w2) r))])))
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;; Matcher × (Value → Matcher) → Matcher
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|
@ -523,11 +557,12 @@
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[#f #f]
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[(success v) (error 'matcher-append "Ill-formed matcher: ~v" m0)]
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[(wildcard-sequence m1) (rwildseq (walk m1))]
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[(? hash?) (for/fold [(acc (rwild (walk (rlookup m ? #f))))]
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[((k v) (in-hash m)) #:when (not (eq? k ?))]
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(if (and (key-close? k) (success? v))
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(matcher-union acc (m-tail-fn (success-value v)))
|
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(rupdate acc k (walk v))))])))
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[(? sorted-map?) (for/fold [(acc (rwild (walk (rlookup m ? #f))))]
|
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[(kv (sorted-map-to-alist m)) #:when (not (eq? (car kv) ?))]
|
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(match-define (cons k v) kv)
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(if (and (key-close? k) (success? v))
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(matcher-union acc (m-tail-fn (success-value v)))
|
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(rupdate acc k (walk v))))])))
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;; Matcher (Value -> (Option Value)) -> Matcher
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;; Maps f over success values in m.
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|
@ -537,9 +572,9 @@
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[#f #f]
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[(success v) (rsuccess (f v))]
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[(wildcard-sequence m1) (rwildseq (walk m1))]
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[(? hash?) (for/fold [(acc (rwild (walk (rlookup m ? #f))))]
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[((k v) (in-hash m)) #:when (not (eq? k ?))]
|
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(rupdate acc k (walk v)))])))
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[(? sorted-map?) (for/fold [(acc (rwild (walk (rlookup m ? #f))))]
|
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[(kv (sorted-map-to-alist m)) #:when (not (eq? (car kv) ?))]
|
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(rupdate acc (car kv) (walk (cdr kv))))])))
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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;; Projection
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|
@ -561,12 +596,12 @@
|
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[(cons p1 p2) (cons SOL (walk p1 (walk-pair-chain p2 acc)))]
|
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[(? vector? v) (cons SOV (vector-foldr walk (cons EOS acc) v))]
|
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[(embedded-matcher m) (error 'compile-projection "Cannot embed matcher in projection")]
|
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;; TODO: consider options for treating sorted-maps as compounds rather than (useless) atoms
|
||||
[(? sorted-map?) (error 'compile-projection "Cannot match on sorted-maps at present")]
|
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[(? non-object-struct?)
|
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(cons (struct->struct-type p)
|
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(walk-pair-chain (cdr (vector->list (struct->vector p)))
|
||||
acc))]
|
||||
;; TODO: consider options for treating hash tables as compounds rather than (useless) atoms
|
||||
[(? hash?) (error 'compile-projection "Cannot match on hash tables at present")]
|
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[other (cons other acc)]))
|
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|
||||
(walk-pair-chain ps0 '()))
|
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|
@ -584,12 +619,12 @@
|
|||
[(capture sub) sub] ;; TODO: maybe enforce non-nesting here too?
|
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[(cons p1 p2) (cons (walk p1) (walk p2))]
|
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[(? vector? v) (for/vector [(e (in-vector v))] (walk e))]
|
||||
;; TODO: consider options for treating sorted-maps as compounds
|
||||
;; rather than (useless) atoms
|
||||
[(? sorted-map?) (error 'projection->pattern "Cannot match on sorted-maps at present")]
|
||||
[(? non-object-struct?)
|
||||
(apply (struct-type-make-constructor (struct->struct-type p))
|
||||
(map walk (cdr (vector->list (struct->vector p)))))]
|
||||
;; TODO: consider options for treating hash tables as compounds
|
||||
;; rather than (useless) atoms
|
||||
[(? hash?) (error 'projection->pattern "Cannot match on hash tables at present")]
|
||||
[other other])))
|
||||
|
||||
;; Matcher × CompiledProjection -> Matcher
|
||||
|
@ -619,14 +654,14 @@
|
|||
[(cons (== ?) k)
|
||||
(match m
|
||||
[(wildcard-sequence _) (add-wild (walk m k))]
|
||||
[(? hash?)
|
||||
(for/fold [(acc (add-wild (walk (rlookup m ? #f) k)))] [((key mk) (in-hash m))]
|
||||
(if (eq? key ?)
|
||||
acc
|
||||
(add-edge acc key (cond
|
||||
[(key-open? key) (balanced mk (lambda (mk) (walk mk k)))]
|
||||
[(key-close? key) #f]
|
||||
[else (walk mk k)]))))]
|
||||
[(? sorted-map?)
|
||||
(for/fold [(acc (add-wild (walk (rlookup m ? #f) k)))]
|
||||
[(key-mk (sorted-map-to-alist m)) #:when (not (eq? (car key-mk) ?))]
|
||||
(match-define (cons key mk) key-mk)
|
||||
(add-edge acc key (cond
|
||||
[(key-open? key) (balanced mk (lambda (mk) (walk mk k)))]
|
||||
[(key-close? key) #f]
|
||||
[else (walk mk k)])))]
|
||||
[_ (matcher-empty)])]
|
||||
|
||||
[(cons sigma k)
|
||||
|
@ -637,21 +672,21 @@
|
|||
[(key-open? sigma) (walk (rwildseq m) k)]
|
||||
[(key-close? sigma) (walk mk k)]
|
||||
[else (walk m k)])]
|
||||
[(? hash?) (walk (rlookup m sigma (rlookup m ? #f)) k)]
|
||||
[(? sorted-map?) (walk (rlookup m sigma (rlookup m ? #f)) k)]
|
||||
[_ (matcher-empty)]))])))
|
||||
|
||||
(define (general-balanced add-wildseq add-wild add-edge m k)
|
||||
(let walk ((m m) (k k))
|
||||
(match m
|
||||
[(wildcard-sequence mk) (add-wildseq (k mk))]
|
||||
[(? hash?)
|
||||
(for/fold [(acc (add-wild (walk (rlookup m ? #f) k)))] [((key mk) (in-hash m))]
|
||||
(if (eq? key ?)
|
||||
acc
|
||||
(add-edge acc key (cond
|
||||
[(key-open? key) (walk mk (lambda (mk) (walk mk k)))]
|
||||
[(key-close? key) (k mk)]
|
||||
[else (walk mk k)]))))]
|
||||
[(? sorted-map?)
|
||||
(for/fold [(acc (add-wild (walk (rlookup m ? #f) k)))]
|
||||
[(key-mk (sorted-map-to-alist m)) #:when (not (eq? (car key-mk) ?))]
|
||||
(match-define (cons key mk) key-mk)
|
||||
(add-edge acc key (cond
|
||||
[(key-open? key) (walk mk (lambda (mk) (walk mk k)))]
|
||||
[(key-close? key) (k mk)]
|
||||
[else (walk mk k)])))]
|
||||
[_ (matcher-empty)])))
|
||||
|
||||
drop-match))
|
||||
|
@ -679,9 +714,10 @@
|
|||
(define (walk m k)
|
||||
(match m
|
||||
[(wildcard-sequence _) #f]
|
||||
[(? hash?)
|
||||
(and (not (hash-has-key? m ?))
|
||||
(for/fold [(acc (set))] [((key mk) (in-hash m))]
|
||||
[(? sorted-map?)
|
||||
(and (not (sorted-map-has-key? m ?))
|
||||
(for/fold [(acc (set))] [(key-mk (sorted-map-to-alist m))]
|
||||
(match-define (cons key mk) key-mk)
|
||||
(maybe-union
|
||||
acc
|
||||
(cond
|
||||
|
@ -702,9 +738,10 @@
|
|||
(define (walk-seq m k)
|
||||
(match m
|
||||
[(wildcard-sequence _) #f]
|
||||
[(? hash?)
|
||||
(and (not (hash-has-key? m ?))
|
||||
(for/fold [(acc (set))] [((key mk) (in-hash m))]
|
||||
[(? sorted-map?)
|
||||
(and (not (sorted-map-has-key? m ?))
|
||||
(for/fold [(acc (set))] [(key-mk (sorted-map-to-alist m))]
|
||||
(match-define (cons key mk) key-mk)
|
||||
(maybe-union acc (cond
|
||||
[(key-close? key) (k (set '()) mk)]
|
||||
[else (walk (rseq key mk)
|
||||
|
@ -756,10 +793,11 @@
|
|||
(d "{")
|
||||
(d vs)
|
||||
(d "}")]
|
||||
[(? hash? h)
|
||||
(if (zero? (hash-count h))
|
||||
(d " ::: empty hash!")
|
||||
(for/fold [(need-sep? #f)] [((key k) (in-hash h))]
|
||||
[(? sorted-map? h)
|
||||
(if (zero? (sorted-map-size h))
|
||||
(d " ::: empty sorted-map!")
|
||||
(for/fold [(need-sep? #f)] [(key-k (sorted-map-to-alist h))]
|
||||
(match-define (cons key k) key-k)
|
||||
(when need-sep?
|
||||
(newline port)
|
||||
(d (make-string i #\space)))
|
||||
|
@ -790,16 +828,18 @@
|
|||
[#f '()]
|
||||
[(success v) (list "" (success->jsexpr v))]
|
||||
[(wildcard-sequence m1) (list "...)" (walk m1))]
|
||||
[(? hash?) (for/list [((k v) (in-hash m))]
|
||||
(list (match k
|
||||
[(== ?) (list "__")]
|
||||
[(== SOL) (list "(")]
|
||||
[(== SOV) (list "#(")]
|
||||
[(== EOS) (list ")")]
|
||||
[(? struct-type? t)
|
||||
(list (string-append (symbol->string (struct-type-name t)) "("))]
|
||||
[else k])
|
||||
(walk v)))])))
|
||||
[(? sorted-map?)
|
||||
(for/list [(kv (sorted-map-to-alist m))]
|
||||
(match-define (cons k v) kv)
|
||||
(list (match k
|
||||
[(== ?) (list "__")]
|
||||
[(== SOL) (list "(")]
|
||||
[(== SOV) (list "#(")]
|
||||
[(== EOS) (list ")")]
|
||||
[(? struct-type? t)
|
||||
(list (string-append (symbol->string (struct-type-name t)) "("))]
|
||||
[else k])
|
||||
(walk v)))])))
|
||||
|
||||
;; String -> String
|
||||
;; Undoes the encoding of struct-type names used in the JSON serialization of Matchers.
|
||||
|
@ -817,25 +857,26 @@
|
|||
[(list "" vj) (rsuccess (jsexpr->success vj))]
|
||||
[(list "...)" j1) (rwildseq (walk j1))]
|
||||
[(list (list kjs vjs) ...)
|
||||
(canonicalize
|
||||
(for/hash [(kj kjs) (vj vjs)]
|
||||
(values (match kj
|
||||
[(list "__") ?]
|
||||
[(list "(") SOL]
|
||||
[(list "#(") SOV]
|
||||
[(list ")") EOS]
|
||||
[(list (? string? s))
|
||||
(match (deserialize-struct-type-name s)
|
||||
[#f (error 'jsexpr->matcher
|
||||
"Illegal open-parenthesis mark ~v"
|
||||
kj)]
|
||||
[tn (match (struct-type-name->struct-type tn)
|
||||
[#f (error 'jsexpr->matcher
|
||||
"Unexpected struct type ~v"
|
||||
tn)]
|
||||
[t t])])]
|
||||
[other other])
|
||||
(walk vj))))])))
|
||||
(for/fold [(acc empty-smap)]
|
||||
[(kj kjs) (vj vjs)]
|
||||
(sorted-map-insert acc
|
||||
(match kj
|
||||
[(list "__") ?]
|
||||
[(list "(") SOL]
|
||||
[(list "#(") SOV]
|
||||
[(list ")") EOS]
|
||||
[(list (? string? s))
|
||||
(match (deserialize-struct-type-name s)
|
||||
[#f (error 'jsexpr->matcher
|
||||
"Illegal open-parenthesis mark ~v"
|
||||
kj)]
|
||||
[tn (match (struct-type-name->struct-type tn)
|
||||
[#f (error 'jsexpr->matcher
|
||||
"Unexpected struct type ~v"
|
||||
tn)]
|
||||
[t t])])]
|
||||
[other other])
|
||||
(walk vj)))])))
|
||||
|
||||
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
|
||||
|
||||
|
@ -1180,39 +1221,32 @@
|
|||
|
||||
(check-requal? (intersect (a 'a) (b 'a)) #f)
|
||||
|
||||
(check-exn #px"Cannot match on hash tables at present"
|
||||
(check-exn #px"Cannot match on sorted-maps at present"
|
||||
(lambda ()
|
||||
(intersect (canonicalize (hash 'a 1 'b ?))
|
||||
(canonicalize (hash 'a ? 'b 2)))))
|
||||
;; (check-requal? (intersect (rseq 'a 1 'b ?) (rseq 'a ? 'b 2)) (rseq 'a 1 'b 2))
|
||||
;; (check-requal? (intersect (rseq 'a 1 'b ?) (rseq 'a ?)) (void))
|
||||
;; (check-requal? (intersect (rseq 'a 1 'b ?) (rseq 'a 1 'b ?)) (rseq 'a 1 'b ?))
|
||||
;; (check-requal? (intersect (rseq 'a 1 'b ?) (rseq 'a ? 'c ?)) (void))
|
||||
(define (h a b c d)
|
||||
(sorted-map-insert (sorted-map-insert empty-smap a b) c d))
|
||||
(intersect (h 'a 1 'b ?)
|
||||
(h 'a ? 'b 2))))
|
||||
|
||||
;; (check-requal? (intersect (rseq 'a 1 'b ?) (rseq 'a 1 'b (list 2 ?)))
|
||||
;; (rseq 'a 1 'b (list 2 ?)))
|
||||
;; (check-requal? (intersect (rseq 'a 1 'b (list ? 3)) (rseq 'a 1 'b (list 2 ?)))
|
||||
;; (rseq 'a 1 'b (list 2 3)))
|
||||
|
||||
(let ((H rseq-multi))
|
||||
(newline)
|
||||
(printf "Checking that intersection with wildcard is identity-like\n")
|
||||
(define m1 (pretty-print-matcher*
|
||||
(foldr matcher-union (matcher-empty)
|
||||
(list (pattern->matcher SA (list 'a ?))
|
||||
(pattern->matcher SB (list 'b ?))
|
||||
(pattern->matcher SC (list 'b 'c))))))
|
||||
(define m2 (pretty-print-matcher* (pattern->matcher SD ?)))
|
||||
(define mi (pretty-print-matcher* (matcher-intersect m1 m2)))
|
||||
(check-requal? mi
|
||||
(H SOL (H 'a (H ? (H EOS (E (set 'A 'D))))
|
||||
'b (H ? (H EOS (E (set 'B 'D)))
|
||||
'c (H EOS (E (set 'B 'C 'D)))))))
|
||||
(check-requal? (pretty-print-matcher*
|
||||
(parameterize ((matcher-intersect-successes (lambda (v1 v2) v1)))
|
||||
(matcher-intersect m1 m2)))
|
||||
m1))
|
||||
)
|
||||
(let ((H rseq-multi))
|
||||
(newline)
|
||||
(printf "Checking that intersection with wildcard is identity-like\n")
|
||||
(define m1 (pretty-print-matcher*
|
||||
(foldr matcher-union (matcher-empty)
|
||||
(list (pattern->matcher SA (list 'a ?))
|
||||
(pattern->matcher SB (list 'b ?))
|
||||
(pattern->matcher SC (list 'b 'c))))))
|
||||
(define m2 (pretty-print-matcher* (pattern->matcher SD ?)))
|
||||
(define mi (pretty-print-matcher* (matcher-intersect m1 m2)))
|
||||
(check-requal? mi
|
||||
(H SOL (H 'a (H ? (H EOS (E (set 'A 'D))))
|
||||
'b (H ? (H EOS (E (set 'B 'D)))
|
||||
'c (H EOS (E (set 'B 'C 'D)))))))
|
||||
(check-requal? (pretty-print-matcher*
|
||||
(parameterize ((matcher-intersect-successes (lambda (v1 v2) v1)))
|
||||
(matcher-intersect m1 m2)))
|
||||
m1))
|
||||
)
|
||||
|
||||
(module+ test
|
||||
(define (matcher-match-matcher-list m1 m2)
|
||||
|
@ -1411,13 +1445,13 @@
|
|||
(pattern->matcher SD (list ? 3))
|
||||
(pattern->matcher SB (list 3 4)))))
|
||||
(S '((("(")
|
||||
((("__") ((2 (((")") (((")") ("" ("A")))))))
|
||||
(3 (((")") (((")") ("" ("D")))))))))
|
||||
(1 ((2 (((")") (((")") ("" ("A")))))))
|
||||
((1 ((2 (((")") (((")") ("" ("A")))))))
|
||||
(3 (((")") (((")") ("" ("D" "C")))))))))
|
||||
(3 ((2 (((")") (((")") ("" ("A")))))))
|
||||
(3 (((")") (((")") ("" ("D")))))))
|
||||
(4 (((")") (((")") ("" ("B"))))))))))))))
|
||||
(4 (((")") (((")") ("" ("B")))))))))
|
||||
(("__") ((2 (((")") (((")") ("" ("A")))))))
|
||||
(3 (((")") (((")") ("" ("D"))))))))))))))
|
||||
(check-equal? (matcher->jsexpr M (lambda (v) (map symbol->string (set->list v)))) S)
|
||||
(check-requal? (jsexpr->matcher S (lambda (v) (list->set (map string->symbol v)))) M)))
|
||||
|
||||
|
|
|
@ -0,0 +1,478 @@
|
|||
#lang racket/base
|
||||
;; Matt Might's red-black tree code from
|
||||
;; http://matt.might.net/articles/red-black-delete/code/sorted-map.rkt
|
||||
;;
|
||||
;; Modified by Tony Garnock-Jones, July 2014:
|
||||
;; - trees are hashconsed
|
||||
;; - sorted-map-size is made constant-time
|
||||
|
||||
(provide (struct-out sorted-map)
|
||||
sorted-map-empty
|
||||
sorted-map-modify-at
|
||||
sorted-map-insert
|
||||
sorted-map-insert*
|
||||
sorted-map-to-tree
|
||||
sorted-map-to-alist
|
||||
sorted-map-submap?
|
||||
sorted-map-get
|
||||
sorted-map-size
|
||||
sorted-map-max
|
||||
sorted-map-delete
|
||||
sorted-map-has-key?
|
||||
sorted-map-keys
|
||||
sorted-map-values
|
||||
)
|
||||
|
||||
(require "canonicalize.rkt")
|
||||
(require "memoize.rkt")
|
||||
(require racket/set)
|
||||
|
||||
; A purely functional sorted-map library.
|
||||
|
||||
; Provides logarithmic insert, update, get & delete.
|
||||
|
||||
; Based on Okasaki's red-black trees
|
||||
; with purely functional red-black delete.
|
||||
|
||||
; Author: Matthew Might
|
||||
; Site: http://matt.might.net/
|
||||
; Page: http://matt.might.net/articles/red-black-delete/
|
||||
|
||||
(require (except-in racket/match define/match))
|
||||
|
||||
; Syntactic sugar for define forms
|
||||
; with match as their body:
|
||||
(define-syntax define/match
|
||||
(syntax-rules ()
|
||||
[(_ (id name) clause ...)
|
||||
; =>
|
||||
(define (id name)
|
||||
(match name clause ...))]))
|
||||
|
||||
(define-syntax define/match*
|
||||
(syntax-rules ()
|
||||
[(_ (id name ...) clause ...)
|
||||
; =>
|
||||
(define (id name ...)
|
||||
(match* (name ...)
|
||||
clause ...))]))
|
||||
|
||||
; A form for matching the result of a comparison:
|
||||
;; tonyg 20140718: changed to use the order? convention from data/order
|
||||
(define-syntax switch-compare
|
||||
(syntax-rules (= < >)
|
||||
[(_ (cmp v1 v2)
|
||||
[< action1 ...]
|
||||
[= action2 ...]
|
||||
[> action3 ...])
|
||||
; =>
|
||||
(let ((dir (cmp v1 v2)))
|
||||
(case dir
|
||||
[(<) action1 ...]
|
||||
[(=) action2 ...]
|
||||
[(>) action3 ...]))]))
|
||||
|
||||
;; tonyg 20140718: for hash-consing, we have to be able to compare
|
||||
;; trees using equal?, which necessitates use of #:transparent in our
|
||||
;; struct definitions.
|
||||
|
||||
; Struct definition for sorted-map:
|
||||
(define-struct sorted-map (compare) #:transparent)
|
||||
|
||||
; Internal nodes:
|
||||
(define-struct (T sorted-map)
|
||||
(color left key value right) #:transparent)
|
||||
|
||||
; Leaf nodes:
|
||||
(define-struct (L sorted-map) () #:transparent)
|
||||
|
||||
; Double-black leaf nodes:
|
||||
(define-struct (BBL sorted-map) () #:transparent)
|
||||
|
||||
|
||||
; Color manipulators.
|
||||
|
||||
; Turns a node black.
|
||||
(define/match (blacken node)
|
||||
[(T cmp _ l k v r) (canonicalize (T cmp 'B l k v r))]
|
||||
[(BBL cmp) (canonicalize (L cmp))]
|
||||
[(L _) node])
|
||||
|
||||
; Turns a node red.
|
||||
(define/match (redden node)
|
||||
[(T cmp _ l k v r) (canonicalize (T cmp 'R l k v r))]
|
||||
[(L _) (error "Can't redden leaf.")])
|
||||
|
||||
|
||||
; Color arithmetic.
|
||||
(define/match (black+1 color-or-node)
|
||||
[(T cmp c l k v r) (canonicalize (T cmp (black+1 c) l k v r))]
|
||||
[(L cmp) (canonicalize (BBL cmp))]
|
||||
['-B 'R]
|
||||
['R 'B]
|
||||
['B 'BB])
|
||||
|
||||
(define/match (black-1 color-or-node)
|
||||
[(T cmp c l k v r) (canonicalize (T cmp (black-1 c) l k v r))]
|
||||
[(BBL cmp) (canonicalize (L cmp))]
|
||||
['R '-B]
|
||||
['B 'R]
|
||||
['BB 'B])
|
||||
|
||||
|
||||
|
||||
; Creates an empty map:
|
||||
(define (sorted-map-empty compare)
|
||||
(canonicalize (L compare)))
|
||||
|
||||
|
||||
;; Custom patterns.
|
||||
|
||||
; Matches internal nodes:
|
||||
(define-match-expander T!
|
||||
(syntax-rules ()
|
||||
[(_) (T _ _ _ _ _ _)]
|
||||
[(_ l r) (T _ _ l _ _ r)]
|
||||
[(_ c l r) (T _ c l _ _ r)]
|
||||
[(_ l k v r) (T _ _ l k v r)]
|
||||
[(_ c l k v r) (T _ c l k v r)]))
|
||||
|
||||
; Matches leaf nodes:
|
||||
(define-match-expander L!
|
||||
(syntax-rules ()
|
||||
[(_) (L _)]))
|
||||
|
||||
; Matches black nodes (leaf or internal):
|
||||
(define-match-expander B
|
||||
(syntax-rules ()
|
||||
[(_) (or (T _ 'B _ _ _ _)
|
||||
(L _))]
|
||||
[(_ cmp) (or (T cmp 'B _ _ _ _)
|
||||
(L cmp))]
|
||||
[(_ l r) (T _ 'B l _ _ r)]
|
||||
[(_ l k v r) (T _ 'B l k v r)]
|
||||
[(_ cmp l k v r) (T cmp 'B l k v r)]))
|
||||
|
||||
; Matches red nodes:
|
||||
(define-match-expander R
|
||||
(syntax-rules ()
|
||||
[(_) (T _ 'R _ _ _ _)]
|
||||
[(_ cmp) (T cmp 'R _ _ _ _)]
|
||||
[(_ l r) (T _ 'R l _ _ r)]
|
||||
[(_ l k v r) (T _ 'R l k v r)]
|
||||
[(_ cmp l k v r) (T cmp 'R l k v r)]))
|
||||
|
||||
; Matches negative black nodes:
|
||||
(define-match-expander -B
|
||||
(syntax-rules ()
|
||||
[(_) (T _ '-B _ _ _ _)]
|
||||
[(_ cmp) (T cmp '-B _ _ _ _)]
|
||||
[(_ l k v r) (T _ '-B l k v r)]
|
||||
[(_ cmp l k v r) (T cmp '-B l k v r)]))
|
||||
|
||||
; Matches double-black nodes (leaf or internal):
|
||||
(define-match-expander BB
|
||||
(syntax-rules ()
|
||||
[(_) (or (T _ 'BB _ _ _ _)
|
||||
(BBL _))]
|
||||
[(_ cmp) (or (T cmp 'BB _ _ _ _)
|
||||
(BBL _))]
|
||||
[(_ l k v r) (T _ 'BB l k v r)]
|
||||
[(_ cmp l k v r) (T cmp 'BB l k v r)]))
|
||||
|
||||
(define/match (double-black? node)
|
||||
[(BB) #t]
|
||||
[_ #f])
|
||||
|
||||
|
||||
; Turns a black-balanced tree with invalid colors
|
||||
; into a black-balanced tree with valid colors:
|
||||
(define (balance-node node)
|
||||
(define cmp (sorted-map-compare node))
|
||||
(match node
|
||||
[(or (T! (or 'B 'BB) (R (R a xk xv b) yk yv c) zk zv d)
|
||||
(T! (or 'B 'BB) (R a xk xv (R b yk yv c)) zk zv d)
|
||||
(T! (or 'B 'BB) a xk xv (R (R b yk yv c) zk zv d))
|
||||
(T! (or 'B 'BB) a xk xv (R b yk yv (R c zk zv d))))
|
||||
; =>
|
||||
(canonicalize (T cmp
|
||||
(black-1 (T-color node))
|
||||
(canonicalize (T cmp 'B a xk xv b))
|
||||
yk
|
||||
yv
|
||||
(canonicalize (T cmp 'B c zk zv d))))]
|
||||
|
||||
[(BB a xk xv (-B (B b yk yv c) zk zv (and d (B))))
|
||||
; =>
|
||||
(canonicalize (T cmp
|
||||
'B
|
||||
(canonicalize (T cmp 'B a xk xv b))
|
||||
yk
|
||||
yv
|
||||
(balance cmp 'B c zk zv (redden d))))]
|
||||
|
||||
[(BB (-B (and a (B)) xk xv (B b yk yv c)) zk zv d)
|
||||
; =>
|
||||
(canonicalize (T cmp
|
||||
'B
|
||||
(balance cmp 'B (redden a) xk xv b)
|
||||
yk
|
||||
yv
|
||||
(canonicalize (T cmp 'B c zk zv d))))]
|
||||
|
||||
[else node]))
|
||||
|
||||
(define (balance cmp c l k v r)
|
||||
(balance-node (canonicalize (T cmp c l k v r))))
|
||||
|
||||
|
||||
; Moves to a location in the map and
|
||||
; peformes an update with the function:
|
||||
;; tonyg 20140718 added on-missing argument
|
||||
(define (sorted-map-modify-at node key f [on-missing (lambda () #f)])
|
||||
|
||||
(define (internal-modify-at node key f)
|
||||
(match node
|
||||
[(T cmp c l k v r)
|
||||
; =>
|
||||
(switch-compare (cmp key k)
|
||||
[< (balance cmp c (internal-modify-at l key f) k v r)]
|
||||
[= (canonicalize (T cmp c l k (f k v) r))]
|
||||
[> (balance cmp c l k v (internal-modify-at r key f))])]
|
||||
|
||||
[(L cmp)
|
||||
; =>
|
||||
(canonicalize (T cmp 'R node key (f key (on-missing)) node))]))
|
||||
|
||||
(blacken (internal-modify-at node key f)))
|
||||
|
||||
|
||||
; Inserts an element into the map
|
||||
(define (sorted-map-insert node key value)
|
||||
(sorted-map-modify-at node key (lambda (k v) value)))
|
||||
|
||||
|
||||
; Inserts several elements into the map:
|
||||
(define (sorted-map-insert* node keys values)
|
||||
(if (or (not (pair? keys))
|
||||
(not (pair? values)))
|
||||
node
|
||||
(sorted-map-insert*
|
||||
(sorted-map-insert node (car keys) (car values))
|
||||
(cdr keys) (cdr values))))
|
||||
|
||||
|
||||
; Coverts a sorted map into a tree:
|
||||
(define/match (sorted-map-to-tree node)
|
||||
[(L!) 'L]
|
||||
[(T! c l k v r) `(,c ,(sorted-map-to-tree l) ,k ,v ,(sorted-map-to-tree r))]
|
||||
[else node])
|
||||
|
||||
|
||||
; Converts a sorted map into an alist:
|
||||
(define (sorted-map-to-alist node)
|
||||
|
||||
(define (sorted-map-prepend-as-alist node alist)
|
||||
(match node
|
||||
[(T! l k v r)
|
||||
; =>
|
||||
(sorted-map-prepend-as-alist
|
||||
l
|
||||
(cons (cons k v)
|
||||
(sorted-map-prepend-as-alist r alist)))]
|
||||
|
||||
[(L _)
|
||||
; =>
|
||||
alist]))
|
||||
|
||||
(sorted-map-prepend-as-alist node '()))
|
||||
|
||||
|
||||
; Tests whether this map is a submap of another map:
|
||||
(define (sorted-map-submap? map1 map2 #:by [by equal?])
|
||||
(define amap1 (sorted-map-to-alist map1))
|
||||
(define amap2 (sorted-map-to-alist map2))
|
||||
(define cmp (sorted-map-compare map1))
|
||||
|
||||
(define (compare-alists amap1 amap2)
|
||||
(match* (amap1 amap2)
|
||||
[(`((,k1 . ,v1) . ,rest1)
|
||||
`((,k2 . ,v2) . ,rest2))
|
||||
; =>
|
||||
(switch-compare (cmp k1 k2)
|
||||
[< #f]
|
||||
[= (and (by v1 v2) (compare-alists rest1 rest2))]
|
||||
[> (compare-alists amap1 rest2)])]
|
||||
|
||||
[('() '()) #t]
|
||||
|
||||
[(_ '()) #f]
|
||||
|
||||
[('() _) #t]))
|
||||
|
||||
(compare-alists amap1 amap2))
|
||||
|
||||
|
||||
; Gets an element from a sorted map:
|
||||
;; tonyg 20140718 add on-missing argument
|
||||
(define (sorted-map-get node key [on-missing (lambda () #f)])
|
||||
(let walk ((node node))
|
||||
(match node
|
||||
[(L!) (on-missing)]
|
||||
|
||||
[(T cmp c l k v r)
|
||||
; =>
|
||||
(switch-compare (cmp key k)
|
||||
[< (walk l)]
|
||||
[= v]
|
||||
[> (walk r)])])))
|
||||
|
||||
|
||||
; Returns the size of the sorted map:
|
||||
;; tonyg 20140718 this is memoized to run in O(1) for every smap
|
||||
(define sorted-map-size
|
||||
(memoize1
|
||||
(lambda (smap)
|
||||
(match smap
|
||||
[(T! l r) (+ 1 (sorted-map-size l)
|
||||
(sorted-map-size r))]
|
||||
[(L!) 0]))))
|
||||
|
||||
|
||||
; Returns the maxium (key . value) pair:
|
||||
(define/match (sorted-map-max node)
|
||||
[(T! _ k v (L!)) (cons k v)]
|
||||
[(T! _ r) (sorted-map-max r)])
|
||||
|
||||
|
||||
; Performs a check to see if both invariants are met:
|
||||
(define (sorted-map-is-legal? node)
|
||||
|
||||
; Calculates the max black nodes on path:
|
||||
(define/match (max-black-height node)
|
||||
[(T! c l r)
|
||||
; =>
|
||||
(+ (if (eq? c 'B) 1 0) (max (max-black-height l)
|
||||
(max-black-height r)))]
|
||||
|
||||
[(L!) 1])
|
||||
|
||||
; Calculates the min black nodes on a path:
|
||||
(define/match (min-black-height node)
|
||||
[(T! c l r)
|
||||
; =>
|
||||
(+ (if (eq? c 'B) 1 0) (min (min-black-height l)
|
||||
(min-black-height r)))]
|
||||
|
||||
[(L!) 1])
|
||||
|
||||
; Is this tree black-balanced?
|
||||
(define (black-balanced? node)
|
||||
(= (max-black-height node)
|
||||
(min-black-height node)))
|
||||
|
||||
; Does this tree contain a red child of red?
|
||||
(define/match (no-red-red? node)
|
||||
[(or (B l r)
|
||||
(R (and l (B)) (and r (B))))
|
||||
; =>
|
||||
(and (no-red-red? l) (no-red-red? r))]
|
||||
|
||||
[(L!) #t]
|
||||
[else #f])
|
||||
|
||||
(let ((colored? (no-red-red? node))
|
||||
(balanced? (black-balanced? node)))
|
||||
(and colored? balanced?)))
|
||||
|
||||
|
||||
; Deletes a key from this map:
|
||||
(define (sorted-map-delete node key)
|
||||
|
||||
(define cmp (sorted-map-compare node))
|
||||
|
||||
; Finds the node to be removed:
|
||||
(define/match (del node)
|
||||
[(T! c l k v r)
|
||||
; =>
|
||||
(switch-compare (cmp key k)
|
||||
[< (bubble c (del l) k v r)]
|
||||
[= (remove node)]
|
||||
[> (bubble c l k v (del r))])]
|
||||
|
||||
[else node])
|
||||
|
||||
; Removes this node; it might
|
||||
; leave behind a double-black node:
|
||||
(define/match (remove node)
|
||||
; Leaves are easiest to kill:
|
||||
[(R (L!) (L!)) (canonicalize (L cmp))]
|
||||
[(B (L!) (L!)) (canonicalize (BBL cmp))]
|
||||
|
||||
; Killing a node with one child;
|
||||
; parent or child is red:
|
||||
[(or (R child (L!))
|
||||
(R (L!) child))
|
||||
; =>
|
||||
child]
|
||||
|
||||
[(or (B (R l k v r) (L!))
|
||||
(B (L!) (R l k v r)))
|
||||
; =>
|
||||
(canonicalize (T cmp 'B l k v r))]
|
||||
|
||||
; Killing a black node with one black child:
|
||||
[(or (B (L!) (and child (B)))
|
||||
(B (and child (B)) (L!)))
|
||||
; =>
|
||||
(black+1 child)]
|
||||
|
||||
; Killing a node with two sub-trees:
|
||||
[(T! c (and l (T!)) (and r (T!)))
|
||||
; =>
|
||||
(match-let (((cons k v) (sorted-map-max l))
|
||||
(l* (remove-max l)))
|
||||
(bubble c l* k v r))])
|
||||
|
||||
; Kills a double-black, or moves it to the top:
|
||||
(define (bubble c l k v r)
|
||||
(cond
|
||||
[(or (double-black? l) (double-black? r))
|
||||
; =>
|
||||
(balance cmp (black+1 c) (black-1 l) k v (black-1 r))]
|
||||
|
||||
[else (canonicalize (T cmp c l k v r))]))
|
||||
|
||||
; Removes the max node:
|
||||
(define/match (remove-max node)
|
||||
[(T! l (L!)) (remove node)]
|
||||
[(T! c l k v r ) (bubble c l k v (remove-max r))])
|
||||
|
||||
; Delete the key, and color the new root black:
|
||||
(blacken (del node)))
|
||||
|
||||
|
||||
;; tonyg 20140718 True iff key is in node
|
||||
(define (sorted-map-has-key? node key)
|
||||
(let walk ((node node))
|
||||
(match node
|
||||
[(L!) #f]
|
||||
[(T cmp c l k v r)
|
||||
(switch-compare (cmp key k)
|
||||
[< (walk l)]
|
||||
[= #t]
|
||||
[> (walk r)])])))
|
||||
|
||||
;; tonyg 20140718 Retrieve a set of the keys of smap
|
||||
(define (sorted-map-keys smap [empty-set (set)])
|
||||
(let walk ((node smap) (acc empty-set))
|
||||
(match node
|
||||
[(T! l k v r) (walk l (set-add (walk r acc) k))]
|
||||
[(L _) acc])))
|
||||
|
||||
;; tonyg 20140718 Retrieve a list of the values of smap
|
||||
(define (sorted-map-values smap)
|
||||
(let walk ((node smap) (acc '()))
|
||||
(match node
|
||||
[(T! l k v r) (walk l (cons v (walk r acc)))]
|
||||
[(L _) acc])))
|
Loading…
Reference in New Issue