suzanne.soy/beautiful-racket
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

refactoring

Browse Source
This commit is contained in:
Matthew Butterick 2016-06-02 16:45:24 -07:00
parent 12f7a3d332
commit 146e460a8f
2 changed files with 24 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

36
brag/brag/codegen/runtime.rkt
View File

@ -164,32 +164,36 @@ This would be the place to check a syntax property for hiding.
;; Creates an stx out of the rule name and its components.
;; The location information of the rule spans that of its components.
(define (rule-components->syntax rule-name/false #:srcloc [srcloc #f] #:hide-or-splice? [hide-or-splice #f] . componentss)
(define (remove-rule-name cs)
(define (remove-rule-name components-stx)
;; when removing a rule name, we apply it as a syntax property to the remaining elements
;; for possible later usage (aka, why throw away information)
;; todo: distinguish hiding and splicing behavior.
;; when hiding, returned list should be a syntaxed list with the property.
;; when splicing, returned list should be a regualr list, with each element having the property.
(let* ([cs-list (syntax->list cs)]
[rule-name (syntax->datum (car cs-list))]
[elements (cdr cs-list)])
(map (λ(e) (syntax-property e rule-name #t)) elements)))
(define spliced-componentss
;; when hiding, returned list should be a syntaxed list with the property (?)
;; when splicing, returned list should be a regular list, with each element having the property.
(let* ([name+elements (syntax->list components-stx)]
[name-datum (syntax->datum (car name+elements))]
[elements (cdr name+elements)])
(map (λ(e) (syntax-property e name-datum #t)) elements)))
(define componentss-hoisted
(apply append
(for/list ([css (in-list componentss)])
(list
(cond
[(and (pair? css) (eq? (syntax-property (car css) 'hide-or-splice) 'hide))
(list (remove-rule-name (car css)))] ; hidden version still contained in `list`
[(and (pair? css) (or (eq? (syntax-property (car css) 'hide-or-splice) 'splice)
(syntax-property (car css) 'splice-rh-id)))
(remove-rule-name (car css))] ; spliced version is "delisted"
[else css])))))
;; each `css` is a list that's either empty, or has a single syntaxed component list
(let ([components-stx (and (pair? css) (car css))])
(if components-stx
(cond
[(eq? (syntax-property components-stx 'hide-or-splice) 'hide)
(list (remove-rule-name components-stx))] ; hidden version still wrapped in a sub-`list`
[(or (eq? (syntax-property components-stx 'hide-or-splice) 'splice)
(syntax-property components-stx 'splice-rh-id))
(remove-rule-name components-stx)] ; spliced version is "delisted"
[else css])
css))))))
(syntax-property
(datum->syntax #f
(cons
(datum->syntax #f rule-name/false srcloc stx-with-original?-property)
(apply append spliced-componentss))
(apply append componentss-hoisted))
srcloc
stx-with-original?-property)
;; not 'hide-or-splice-lhs-id, because it is now a component in a different rule

8
brag/brag/test/test-baby-json-hider.rkt
View File

@ -4,10 +4,10 @@
rackunit)
(define parse-result (parse (list "{"
(token 'ID "message")
":"
(token 'STRING "'hello world'")
"}")))
(token 'ID "message")
":"
(token 'STRING "'hello world'")
"}")))
(check-equal? (syntax->datum parse-result) '(json ":"))
(define syntaxed-colon (cadr (syntax->list parse-result)))