575 lines
21 KiB
Racket
575 lines
21 KiB
Racket
#lang typed/racket
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(require typed/graph typed-compose typed/racket/stream
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(for-syntax syntax/parse racket/list))
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(provide
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Variable VariableMapping GeneralPair
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eval-with eval1-with auto-hash-ref/explicit auto-hash-ref/:
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extract-symbols any->string stringify-variable-mapping string->any
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handle-org-booleans map-sexp read-org-sexp unorg unstringify-pairs
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read-org-variable-mapping unorgv read-symbol-list drop-first-last
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list-sets->list-strings pretty-print-set pretty-print-set-sets
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update-vertices/unweighted update-graph dotit collect-by-key
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collect-by-key/sets ht-values/list->set hash->list/ordered
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multi-split-at lists-transpose append-lists in-random cartesian-product-2/stream
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cartesian-product/stream boolean-power boolean-power/stream any->01
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01->boolean
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variable-mapping?)
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(module+ test
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(require typed/rackunit))
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(define-type Variable Symbol)
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(define-type (VariableMapping A) (Immutable-HashTable Variable A))
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(: eval-with (-> (VariableMapping Any) Any AnyValues))
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(define (eval-with ht expr)
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(parameterize ([current-namespace (make-base-namespace)])
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(for ([(x val) (in-hash ht)]) (namespace-set-variable-value! x val))
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(eval expr)))
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(: eval1-with (-> (VariableMapping Any) Any Any))
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(define (eval1-with ht expr)
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(call-with-values (λ () (eval-with ht expr))
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(λ args (car args))))
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(module+ test
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(test-case "eval-with"
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(check-equal? (eval1-with (hash 'a 1 'b 2) '(+ a b 1))
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4)
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(define ht : (VariableMapping Integer) (hash 'a 1 'b 2))
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(define expr : Any '(+ a b 1))
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(check-equal? (eval1-with ht expr)
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4)))
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(define-syntax (auto-hash-ref/explicit stx)
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(syntax-parse stx
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[(_ (ht:id keys:id ...) body:expr)
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#`(let #,(for/list ([key (syntax->list #'(keys ...))])
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`[,key (hash-ref ,#'ht ',key)])
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body)]))
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(module+ test
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(test-case "auto-hash-ref/explicit"
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(define mytable #hash((a . 3) (b . 4)))
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(check-equal? (auto-hash-ref/explicit (mytable b a)
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(* a b))
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12)
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(define ht #hash((a . #t) (b . #f)))
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(check-equal? (auto-hash-ref/explicit (ht a b)
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(and (not a) b))
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#f)))
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;;; Helper functions for auto-hash-ref/:.
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(begin-for-syntax
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(define (colon? s)
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(and (symbol? s)
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(eq? (string-ref (symbol->string s) 0) #\:)))
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(define (collect-colons datum)
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(cond [(colon? datum) (list datum)]
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[(list? datum)
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(remove-duplicates (flatten (for/list ([el (in-list datum)])
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(collect-colons el))))]
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[else '()]))
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(define (strip-colon s)
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(string->symbol (substring (symbol->string s) 1))))
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(define-syntax (auto-hash-ref/: stx)
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(syntax-parse stx
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[(_ ht:id body:expr)
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(define colons (collect-colons (syntax->datum stx)))
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(define bindings (for/list ([key colons])
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`[,key (hash-ref ,#'ht ',(strip-colon key))]))
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(with-syntax ([bindings-stx (datum->syntax stx bindings)])
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#'(let bindings-stx body))]))
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(module+ test
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(test-case "auto-hash-ref/:"
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(define ht1 #hash((x . #t) (y . #t) (t . #f)))
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(define z #t)
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(check-equal? (auto-hash-ref/: ht1
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(and :x (not :y) z (or (and :t) :x)))
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#f)
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(define ht2 #hash((a . 1) (b . 2)))
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(check-equal? (auto-hash-ref/: ht2 (+ :a (* 2 :b)))
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5)))
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(: extract-symbols (-> Any (Listof Symbol)))
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(define (extract-symbols form)
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(: extract-rec (-> Any (Listof Any)))
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(define (extract-rec form)
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(match form
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[(? symbol?) (list form)]
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[(? list?)
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(flatten (for/list : (Listof Any)
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([x form])
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(extract-symbols x)))]
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[else '()]))
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(cast (extract-rec form) (Listof Symbol)))
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(module+ test
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(test-case "extract-symbols"
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(check-equal? (extract-symbols '(1 (2 3) x (y z 3)))
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'(x y z))))
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(: any->string (-> Any String))
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(define (any->string x)
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(with-output-to-string (λ () (display x))))
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(module+ test
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(test-case "any->string"
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(check-equal? (any->string 'a) "a")
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(check-equal? (any->string '(a 1 (x y))) "(a 1 (x y))")
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(check-equal? (any->string "hello") "hello")))
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(: stringify-variable-mapping (-> (VariableMapping Any) (VariableMapping String)))
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(define (stringify-variable-mapping ht)
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(for/hash : (VariableMapping String)
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([(key val) (in-hash ht)]) (values key (any->string val))))
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(module+ test
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(test-case "stringify-variable-mapping"
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(define mp (stringify-variable-mapping #hash((a . (and a b)) (b . (not b)))))
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(check-equal? (hash-ref mp 'a) "(and a b)")
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(check-equal? (hash-ref mp 'b) "(not b)")))
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(: string->any (-> String Any))
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(define (string->any str)
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(with-input-from-string str (λ () (read))))
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(module+ test
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(test-case "string->any"
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(check-equal? (string->any "(or b (not a))") '(or b (not a)))
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(check-equal? (string->any "14") 14)))
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;;; Given a sexp, converts all "#f" to #f and "#t" to #t.
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;;;
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;;; When I read Org-mode tables, I pump them through a call to the
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;;; prin1 because the Elisp sexps seems incompatible with Racket.
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;;; On the other hand, Racket Booleans seem to upset Elisp a little,
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;;; so prin1 wraps them in additional double quotes. This function
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;;; removes those quotes.
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(: handle-org-booleans (-> Any Any))
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(define/match (handle-org-booleans datum)
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[("#t") #t]
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[("#f") #f]
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[((? list?)) (map handle-org-booleans datum)]
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[ (_) datum])
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(module+ test
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(test-case "handle-org-booleans"
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(check-equal? (handle-org-booleans "#t") #t)
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(check-equal? (handle-org-booleans "#f") #f)
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(check-equal? (handle-org-booleans '("#t" "#f")) '(#t #f))
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(check-equal? (handle-org-booleans "t") "t")))
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(: map-sexp (-> (-> Any Any) Any Any))
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(define (map-sexp func sexp)
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(match sexp
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[(? list?) (map ((curry map-sexp) func) sexp)]
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[datum (func datum)]))
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(module+ test
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(test-case "map-sexp"
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(check-equal? (map-sexp (λ (x) (add1 (cast x Number))) '(1 2 (4 10) 3))
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'(2 3 (5 11) 4))))
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(: read-org-sexp (-> String Any))
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(define read-org-sexp
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(compose ((curry map-sexp) (match-lambda
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[(and (? string?) str) (string->any str)]
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[x x]))
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string->any))
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(define unorg read-org-sexp)
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(module+ test
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(test-case "read-org-sexp"
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(check-equal? (read-org-sexp "((\"a\" \"(and a b)\") (\"b\" \"(or b (not a))\"))")
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'((a (and a b)) (b (or b (not a)))))
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(check-equal? (unorg "(#t \"#t\" \"#t \" '(1 2 \"#f\"))")
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'(#t #t #t '(1 2 #f)))))
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(define-type (GeneralPair A B) (U (Pair A B) (List A B)))
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(: unstringify-pairs (-> (Listof (GeneralPair String Any))
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(Listof (GeneralPair Symbol Any))))
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(define (unstringify-pairs pairs)
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(for/list ([p pairs])
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(match p
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[(list key val)
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(cons (string->symbol key) (if (string? val)
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(string->any val)
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val))]
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[(cons key val)
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(cons (string->symbol key) (if (string? val)
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(string->any val)
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val))])))
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(module+ test
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(test-case "unstringify-pairs"
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(check-equal? (unstringify-pairs '(("a" . "1") ("b" . "(and a (not b))")))
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'((a . 1) (b . (and a (not b)))))
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(check-equal? (unstringify-pairs '(("a" . 1) ("b" . "(and a (not b))")))
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'((a . 1) (b . (and a (not b)))))))
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(: read-org-variable-mapping (-> String (VariableMapping Any)))
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(define read-org-variable-mapping
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(multi-compose
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(λ ([pairs : (Listof (Pair Symbol Any))])
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(make-immutable-hash pairs))
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(λ (sexp)
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(unstringify-pairs (cast sexp (Listof (GeneralPair String Any)))))
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string->any))
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;;; A synonym for read-org-variable-mapping.
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(define unorgv read-org-variable-mapping)
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(module+ test
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(test-case "read-org-variable-mapping"
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(define m1 (read-org-variable-mapping "((\"a\" \"(and a b)\") (\"b\" \"(or b (not a))\"))"))
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(define m2 (read-org-variable-mapping "((\"a\" . \"(and a b)\") (\"b\" . \"(or b (not a))\"))"))
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(define m3 (unorgv "((\"a\" . \"(and a b)\") (\"b\" . \"(or b (not a))\"))"))
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(check-equal? (hash-ref m1 'a) '(and a b))
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(check-equal? (hash-ref m2 'a) '(and a b))
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(check-equal? (hash-ref m3 'a) '(and a b))
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(check-equal? (hash-ref m1 'b) '(or b (not a)))
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(check-equal? (hash-ref m2 'b) '(or b (not a)))
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(check-equal? (hash-ref m3 'b) '(or b (not a)))))
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(: read-symbol-list (-> String (Listof Symbol)))
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(define (read-symbol-list str)
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(cast (string->any (string-append "(" str ")")) (Listof Symbol)))
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(module+ test
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(test-case "read-symbol-list"
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(check-equal? (read-symbol-list "a b c") '(a b c))))
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(: drop-first-last (-> String String))
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(define (drop-first-last str)
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(substring str 1 (- (string-length str) 1)))
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(module+ test
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(test-case "drop-first-last"
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(check-equal? (drop-first-last "(a b)") "a b")))
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(: list-sets->list-strings (-> (Listof (Setof Any)) (Listof String)))
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(define (list-sets->list-strings lst)
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(map (multi-compose drop-first-last
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any->string
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(λ ([x : (Setof Any)])
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(set->list x))) lst))
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(module+ test
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(test-case "list-sets->list-strings"
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(check-equal? (list-sets->list-strings (list (set 'x 'y) (set 'z) (set) (set 't)))
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'("x y" "z" "" "t"))))
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(: pretty-print-set (-> (Setof Any) String))
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(define (pretty-print-set s)
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(string-join (sort (set-map s any->string) string<?)))
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(module+ test
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(test-case "pretty-print-set"
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(check-equal? (pretty-print-set (set 'a 'b 1)) "1 a b")))
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(: pretty-print-set-sets (-> (Setof (Setof Any)) String))
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(define (pretty-print-set-sets ms)
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(string-join (for/list ([m ms]) : (Listof String)
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(format "{~a}" (pretty-print-set m))) ""))
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(module+ test
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(test-case "pretty-print-set-sets"
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(check-equal? (pretty-print-set-sets (set (set 'a 'b) (set 'c))) "{a b}{c}")))
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(define dotit (compose display graphviz))
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(: update-vertices/unweighted (-> Graph (-> Any Any) Graph))
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(define (update-vertices/unweighted gr func)
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(unweighted-graph/directed
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(for/list ([e (in-edges gr)])
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(match-let ([(list u v) e])
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(list (func u) (func v))))))
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(module+ test
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(test-case "update-vertices/unweighted"
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(define gr1 (directed-graph '((a b) (b c))))
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(define gr2 (undirected-graph '((a b) (b c))))
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(define (dbl [x : Any])
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(define x-str (symbol->string (cast x Symbol)))
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(string->symbol (string-append x-str x-str)))
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(define new-gr1 (update-vertices/unweighted gr1 dbl))
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(define new-gr2 (update-vertices/unweighted gr2 dbl))
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(check-false (has-vertex? new-gr1 'a))
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(check-true (has-vertex? new-gr1 'aa))
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(check-false (has-vertex? new-gr1 'b))
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(check-true (has-vertex? new-gr1 'bb))
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(check-false (has-vertex? new-gr1 'c))
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(check-true (has-vertex? new-gr1 'cc))
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(check-true (has-edge? new-gr1 'aa 'bb))
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(check-true (has-edge? new-gr1 'bb 'cc))
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(check-true (has-edge? new-gr2 'aa 'bb))
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(check-true (has-edge? new-gr2 'bb 'aa))
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(check-true (has-edge? new-gr2 'bb 'cc))
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(check-true (has-edge? new-gr2 'cc 'bb))))
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(: update-graph (->* (Graph) (#:v-func (-> Any Any) #:e-func (-> Any Any)) Graph))
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(define (update-graph gr #:v-func [v-func identity] #:e-func [e-func identity])
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(cond
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[(unweighted-graph? gr)
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(unweighted-graph/directed
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(for/list ([e (in-edges gr)]) : (Listof (List Any Any))
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(match-let ([(list u v) e])
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(list (v-func u) (v-func v)))))]
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[else
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(weighted-graph/directed
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(for/list ([e (in-edges gr)]) : (Listof (List Any Any Any))
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(match-let ([(list u v) e])
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(list (e-func (edge-weight gr u v))
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(v-func u) (v-func v)))))]))
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(module+ test
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(test-case "update-graph"
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(define gr1 (directed-graph '((a b) (b c))))
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(define gr2 (undirected-graph '((a b) (b c))))
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(define (dbl [x : Any])
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(define x-str (symbol->string (cast x Symbol)))
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(string->symbol (string-append x-str x-str)))
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(define new-gr1-ug (update-graph gr1 #:v-func dbl))
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(define new-gr2-ug (update-graph gr2 #:v-func dbl))
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(define gr3 (weighted-graph/directed '((10 a b) (11 b c))))
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(define new-gr3 (update-graph gr3
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#:v-func dbl
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#:e-func (λ (x) (* 2 (cast x Number)))))
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(check-false (has-vertex? new-gr1-ug 'a))
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(check-true (has-vertex? new-gr1-ug 'aa))
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(check-false (has-vertex? new-gr1-ug 'b))
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(check-true (has-vertex? new-gr1-ug 'bb))
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(check-false (has-vertex? new-gr1-ug 'c))
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(check-true (has-vertex? new-gr1-ug 'cc))
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(check-true (has-edge? new-gr1-ug 'aa 'bb))
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(check-true (has-edge? new-gr1-ug 'bb 'cc))
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(check-true (has-edge? new-gr2-ug 'aa 'bb))
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(check-true (has-edge? new-gr2-ug 'bb 'aa))
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(check-true (has-edge? new-gr2-ug 'bb 'cc))
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(check-true (has-edge? new-gr2-ug 'cc 'bb))
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(check-true (has-edge? new-gr3 'aa 'bb))
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(check-false (has-edge? new-gr3 'bb 'aa))
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(check-true (has-edge? new-gr3 'bb 'cc))
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(check-false (has-edge? new-gr3 'cc 'bb))
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(check-equal? (edge-weight new-gr3 'aa 'bb) 20)
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(check-equal? (edge-weight new-gr3 'bb 'cc) 22)))
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(: collect-by-key (All (a b) (-> (Listof a) (Listof b)
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(Values (Listof a) (Listof (Listof b))))))
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(define (collect-by-key keys vals)
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(for/fold ([ht : (HashTable a (Listof b))
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(make-immutable-hash)]
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#:result (values (hash-keys ht) (hash-values ht)))
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([e keys]
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[l vals])
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((inst hash-update a (Listof b)) ht e (λ (ls) (cons l ls)) (λ () empty))))
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(module+ test
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(test-case "collect-by-key"
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(define-values (e1 l1) (collect-by-key '((1 2) (1 3)) '(a b)))
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(define-values (e2 l2) (collect-by-key '((1 2) (1 2)) '(a b)))
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(check-equal? e1 '((1 2) (1 3))) (check-equal? l1 '((a) (b)))
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(check-equal? e2 '((1 2))) (check-equal? l2 '((b a)))))
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(: collect-by-key/sets (All (a b) (-> (Listof a) (Listof b)
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(Values (Listof a) (Listof (Setof b))))))
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(define (collect-by-key/sets edges labels)
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(define-values (es ls) (collect-by-key edges labels))
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(values es ((inst map (Setof b) (Listof b)) list->set ls)))
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(module+ test
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(test-case "collect-by-key/sets"
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(define-values (e3 l3) (collect-by-key/sets '(a b a) '(1 2 1)))
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(check-equal? e3 '(b a)) (check-equal? l3 (list (set 2) (set 1)))))
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;;; Converts the values of a hash table from lists to sets.
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(: ht-values/list->set (All (a b) (-> (HashTable a (Listof b)) (HashTable a (Setof b)))))
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(define (ht-values/list->set ht)
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(for/hash ([(k v) (in-hash ht)]) : (HashTable a (Setof b))
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(values k (list->set v))))
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(module+ test
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(test-case "ht-values/list->set"
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(check-equal? (ht-values/list->set #hash((a . (1 1))))
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(hash 'a (set 1)))))
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;; TODO: Remove after Typed Racket has caught up with Racket 8.4.
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(: hash->list/ordered (All (a b) (-> (HashTable a b) (Listof (Pairof a b)))))
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(define (hash->list/ordered ht)
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((inst hash-map a b (Pairof a b)) ht cons #t))
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(module+ test
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(test-case "hash->list/ordered"
|
||
(check-equal? (hash->list/ordered #hash((b . 1) (a . 1)))
|
||
'((a . 1) (b . 1)))))
|
||
|
||
(: multi-split-at (All (a) (-> (Listof (Listof a)) Integer
|
||
(Values (Listof (Listof a)) (Listof (Listof a))))))
|
||
(define (multi-split-at lists pos)
|
||
(for/fold ([lefts : (Listof (Listof a)) '()]
|
||
[rights : (Listof (Listof a)) '()]
|
||
#:result (values (reverse lefts) (reverse rights)))
|
||
([lst (in-list lists)])
|
||
(define-values (left right) ((inst split-at a) lst pos))
|
||
(values (cons left lefts) (cons right rights))))
|
||
|
||
(module+ test
|
||
(test-case "multi-split-at"
|
||
(define-values (l1 l2) (multi-split-at '((1 2 3) (a b c)) 2))
|
||
(check-equal? l1 '((1 2) (a b))) (check-equal? l2 '((3) (c)))))
|
||
|
||
;; https://racket.discourse.group/t/get-to-type-apply-in-parallel-lst/683
|
||
;;
|
||
;; Same thread: (apply ((curry map) list) lsts), however I don't
|
||
;; feel like typing this right now (2022-02-18).
|
||
(: lists-transpose (All (a ...) (-> (List (Listof a) ... a) (Listof (List a ... a)))))
|
||
(define (lists-transpose lists)
|
||
(sequence->list (in-values-sequence (apply in-parallel lists))))
|
||
|
||
(module+ test
|
||
(test-case "lists-transpose"
|
||
(check-equal? (lists-transpose '((1 2) (a b))) '((1 a) (2 b)))))
|
||
|
||
(: append-lists (All (a) (-> (Listof (List (Listof a) (Listof a))) (Listof (Listof a)))))
|
||
(define (append-lists lsts)
|
||
(for/list ([pr lsts])
|
||
(append (car pr) (cadr pr))))
|
||
|
||
(module+ test
|
||
(test-case "append-lists"
|
||
(check-equal? (append-lists '(((1 2) (a b))
|
||
((3 4) (c d))))
|
||
'((1 2 a b)
|
||
(3 4 c d)))))
|
||
|
||
(: in-random (case->
|
||
(-> (Sequenceof Flonum))
|
||
(-> Integer (Sequenceof Nonnegative-Fixnum))
|
||
(-> Integer Integer (Sequenceof Nonnegative-Fixnum))))
|
||
(define in-random
|
||
(case-lambda
|
||
[() (stream-cons (random) (in-random))]
|
||
[(k) (stream-cons (random k) (in-random k))]
|
||
[(min max) (stream-cons (random min max) (in-random min max))]))
|
||
|
||
(module+ test
|
||
(test-case "in-random"
|
||
(random-seed 1)
|
||
(check-equal? (stream->list (stream-take (in-random 100) 10))
|
||
'(50 84 10 99 94 88 43 41 63 50))
|
||
(check-equal? (stream->list (stream-take (in-random 50 100) 10))
|
||
'(57 98 82 83 61 53 73 82 50 80))
|
||
(check-equal? (stream->list (stream-take (in-random) 10))
|
||
'(0.2718099186980313
|
||
0.7319496826374751
|
||
0.17365244033739616
|
||
0.5593031443038616
|
||
0.3345256691289459
|
||
0.9845704615094365
|
||
0.05753824253751768
|
||
0.22552976312818723
|
||
0.21646500425988832
|
||
0.15188352823997242))))
|
||
|
||
(: cartesian-product-2/stream (All (a b) (-> (Sequenceof a) (Sequenceof b) (Sequenceof (Pair a b)))))
|
||
(define (cartesian-product-2/stream s1 s2)
|
||
(: cp2-store (All (a b) (-> (Sequenceof a) (Sequenceof b) (Sequenceof b)
|
||
(Sequenceof (Pair a b)))))
|
||
;; The recursive implementation using s2-store as an accumulator.
|
||
;; Main idea: combine the elements of s1 with the element of s2
|
||
;; until they are exhausted, then restart with the next element of
|
||
;; s1 and the original content of s2.
|
||
(define (cp2-store s1 s2 s2-store)
|
||
(cond
|
||
[(stream-empty? s1) (stream)]
|
||
[(stream-empty? s2) (cp2-store (stream-rest s1) s2-store s2-store)]
|
||
[else
|
||
(stream-cons (cons (stream-first s1) (stream-first s2))
|
||
(cp2-store s1 (stream-rest s2) s2-store))]))
|
||
(cp2-store s1 s2 s2))
|
||
|
||
(module+ test
|
||
(test-case "cartesian-product-2/stream"
|
||
(check-equal? (stream->list (cartesian-product-2/stream (in-range 1 5) '(a b)))
|
||
'((1 . a) (1 . b) (2 . a) (2 . b) (3 . a) (3 . b) (4 . a) (4 . b)))
|
||
(check-equal?
|
||
(stream->list (stream-take (cartesian-product-2/stream '(a b) (in-naturals)) 10))
|
||
'((a . 0) (a . 1) (a . 2) (a . 3) (a . 4) (a . 5) (a . 6) (a . 7) (a . 8) (a . 9)))))
|
||
|
||
(: cartesian-product/stream (All (a) (-> (Listof (Sequenceof a)) (Sequenceof (Listof a)))))
|
||
(define (cartesian-product/stream ss)
|
||
(for/foldr ([prod (stream (list))])
|
||
([s (in-list ss)])
|
||
(cartesian-product-2/stream s prod)))
|
||
|
||
(module+ test
|
||
(test-case "cartesian-product/stream"
|
||
(check-equal? (stream->list (cartesian-product/stream '())) '(()))
|
||
(check-equal? (stream->list (cartesian-product/stream '((a b c))))
|
||
'((a) (b) (c)))
|
||
(check-equal? (stream->list (cartesian-product/stream (list (in-range 3) (in-range 4 6) '(a b))))
|
||
'((0 4 a)
|
||
(0 4 b)
|
||
(0 5 a)
|
||
(0 5 b)
|
||
(1 4 a)
|
||
(1 4 b)
|
||
(1 5 a)
|
||
(1 5 b)
|
||
(2 4 a)
|
||
(2 4 b)
|
||
(2 5 a)
|
||
(2 5 b)))))
|
||
|
||
(: boolean-power (-> Integer (Listof (Listof Boolean))))
|
||
(define (boolean-power n)
|
||
(apply cartesian-product (make-list n '(#f #t))))
|
||
|
||
(module+ test
|
||
(test-case "boolean-power"
|
||
(check-equal? (boolean-power 2) '((#f #f) (#f #t) (#t #f) (#t #t)))))
|
||
|
||
(: boolean-power/stream (-> Integer (Sequenceof (Listof Boolean))))
|
||
(define (boolean-power/stream n) (cartesian-product/stream (make-list n '(#f #t))))
|
||
|
||
(module+ test
|
||
(test-case "boolean-power/stream"
|
||
(check-equal? (stream->list (boolean-power/stream 2)) '((#f #f) (#f #t) (#t #f) (#t #t)))))
|
||
|
||
(: any->01 (-> Any (U Zero One)))
|
||
(define (any->01 x)
|
||
(if x 1 0))
|
||
|
||
(module+ test
|
||
(test-case "any->01"
|
||
(check-equal? (any->01 #t) 1)
|
||
(check-equal? (any->01 #f) 0)))
|
||
|
||
(: 01->boolean (-> (U Zero One) Boolean))
|
||
(define (01->boolean x)
|
||
(case x [(0) #f] [else #t]))
|
||
|
||
(module+ test
|
||
(test-case "01->boolean"
|
||
(check-equal? (01->boolean 0) #f)
|
||
(check-equal? (01->boolean 1) #t)))
|
||
|
||
;; TODO: Remove when the other modules are converted to Typed Racket
|
||
;; and these contracts are not needed any more.
|
||
|
||
(: variable-mapping? (-> Any Boolean : HashTableTop))
|
||
(define (variable-mapping? dict)
|
||
(hash? dict))
|