From bdf8fd9ed7c3b41b5395b7f97213831fdb0f6e0b Mon Sep 17 00:00:00 2001 From: Matthew Butterick Date: Fri, 11 Dec 2015 14:06:57 -0800 Subject: [PATCH] add comment --- main.rkt | 50 ++++++++++++++++++++++++++++++++++---------------- 1 file changed, 34 insertions(+), 16 deletions(-) diff --git a/main.rkt b/main.rkt index 96847d4..d9ed10f 100644 --- a/main.rkt +++ b/main.rkt @@ -90,7 +90,10 @@ (define+provide+safe (can-be-txexpr-attrs? x) predicate/c - (ormap (λ(test) (test x)) (list txexpr-attr? txexpr-attrs? can-be-txexpr-attr-key? can-be-txexpr-attr-value?))) + (ormap (λ(test) (test x)) (list txexpr-attr? + txexpr-attrs? + can-be-txexpr-attr-key? + can-be-txexpr-attr-value?))) (define+provide+safe (list-of-can-be-txexpr-attrs? xs) @@ -103,14 +106,16 @@ (if (not (list? x)) (format "because ~v is not a list" x) (let ([bad-attrs (filter (λ(i) (not (txexpr-attr? i))) x)]) - (format "because ~a ~a" (string-join (map (λ(ba) (format "~v" ba)) bad-attrs) " and ") (if (> (length bad-attrs) 1) - "are not valid attributes" - "is not in the form '(symbol \"string\")"))))) + (format "because ~a ~a" (string-join (map (λ(ba) (format "~v" ba)) bad-attrs) " and ") + (if (> (length bad-attrs) 1) + "are not valid attributes" + "is not in the form '(symbol \"string\")"))))) (cond [(and (list? x) (> (length x) 0) (andmap txexpr-attr? x)) x] [else (error (string-append "validate-txexpr-attrs: " (if txexpr-context (format "in ~v, " txexpr-context) "") - (format "~v is not a valid list of attributes ~a" x (make-reason))))])) + (format "~v is not a valid list of attributes ~a" x + (make-reason))))])) (define (validate-txexpr-element x #:context [txexpr-context #f]) @@ -126,8 +131,10 @@ ;; todo: rewrite this recurively so errors can be pinpointed (for debugging) (define+provide+safe (validate-txexpr x) (any/c . -> . txexpr?) - (define-syntax-rule (validate-txexpr-attrs-with-context e) (validate-txexpr-attrs e #:context x)) - (define-syntax-rule (validate-txexpr-element-with-context e) (validate-txexpr-element e #:context x)) + (define-syntax-rule (validate-txexpr-attrs-with-context e) + (validate-txexpr-attrs e #:context x)) + (define-syntax-rule (validate-txexpr-element-with-context e) + (validate-txexpr-element e #:context x)) (cond [(txexpr-short? x) x] [(txexpr? x) (and @@ -238,7 +245,9 @@ (define+provide+safe (attr-set tx key value) (txexpr? can-be-txexpr-attr-key? can-be-txexpr-attr-value? . -> . txexpr?) (define new-attrs - (hash->attrs (hash-set (attrs->hash (get-attrs tx)) (->txexpr-attr-key key) (->txexpr-attr-value value)))) + (hash->attrs (hash-set (attrs->hash (get-attrs tx)) + (->txexpr-attr-key key) + (->txexpr-attr-value value)))) (make-txexpr (get-tag tx) new-attrs (get-elements tx))) @@ -278,7 +287,8 @@ (() #:rest list-of-can-be-txexpr-attrs? . ->* . txexpr-attrs?) (define attrs-hash (apply attrs->hash items)) ;; sort needed for predictable results for unit tests - (define sorted-hash-keys (sort (hash-keys attrs-hash) (λ(a b) (stringstring a) (->string b))))) + (define sorted-hash-keys (sort (hash-keys attrs-hash) + (λ(a b) (stringstring a) (->string b))))) `(,@(map (λ(key) (list key (hash-ref attrs-hash key))) sorted-hash-keys))) @@ -320,7 +330,8 @@ (set! matches (cons x matches)) (proc x))] [(txexpr? x) (let-values([(tag attr elements) (txexpr->values x)]) - (make-txexpr tag attr (filter (λ(e) (not (equal? e deleted-signal))) (map do-extraction elements))))] + (make-txexpr tag attr (filter (λ(e) (not (equal? e deleted-signal))) + (map do-extraction elements))))] [else x])) (define tx-extracted (do-extraction tx)) ;; do this first to fill matches (values (if (txexpr? tx-extracted) @@ -333,13 +344,16 @@ (define (->cdata x) (cond [(cdata? x) x] - [(string? x) (cdata #f #f x)] ; don't use "![CDATA[...]]" wrapper in HTML, it's not consistent with the spec + ; don't use "![CDATA[...]]" wrapper in HTML, it's not consistent with the spec + [(string? x) (cdata #f #f x)] [else x])) (xexpr->string (let loop ([x x]) (cond [(txexpr? x) (if (member (get-tag x) '(script style)) - (make-txexpr (get-tag x) (get-attrs x) (map ->cdata (get-elements x))) - (make-txexpr (get-tag x) (get-attrs x) (map loop (get-elements x))))] + (make-txexpr (get-tag x) (get-attrs x) + (map ->cdata (get-elements x))) + (make-txexpr (get-tag x) (get-attrs x) + (map loop (get-elements x))))] [else x])))) (require rackunit) @@ -348,9 +362,11 @@ ;; txexprs are deemed equal if they differ only in the ordering of attributes. ;; therefore, to check them, 1) sort their attributes, 2) straight list comparison. ;; use letrec because `define-simple-check` wants an expression in <=6.2 - + ;; `stringify-attr` is needed because comparing attr keys won't work if there are two attrs with same key. ;; so the whole attr is converted into a single string for sorting, which lets the attr value act as a tiebreaker. + ;; it doesn't matter that this sort may not be correct (in the sense of a desirable ordering) + ;; it just needs to be stable (e.g., a certain set of attrs will always sort the same way) (letrec ([stringify-attr (λ(attr) (string-append (symbol->string (car attr)) (cadr attr)))] [sort-attrs (λ(x) (if (txexpr? x) @@ -359,6 +375,8 @@ x))]) (equal? (sort-attrs tx1) (sort-attrs tx2)))) -(check-txexprs-equal? '(p ((b "foo")(a "bar")) (span ((d "foo")(c "bar")))) '(p ((a "bar")(b "foo")) (span ((c "bar")(d "foo"))))) +(check-txexprs-equal? '(p ((b "foo")(a "bar")) (span ((d "foo")(c "bar")))) + '(p ((a "bar")(b "foo")) (span ((c "bar")(d "foo"))))) ;; two attrs with same key -(check-txexprs-equal? '(p ((a "foo")(a "bar"))) '(p ((a "bar")(a "foo")))) \ No newline at end of file +(check-txexprs-equal? '(p ((a "foo")(a "bar"))) + '(p ((a "bar")(a "foo")))) \ No newline at end of file