racket/collects/unstable/markparam.rkt
2010-04-30 13:06:55 -06:00

41 lines
1.5 KiB
Racket

#lang racket
(require racket/serialize)
(define mark-parameter-first
(curry continuation-mark-set-first #f))
(define (mark-parameter-all mp [prompt-tag (default-continuation-prompt-tag)])
(continuation-mark-set->list (current-continuation-marks) mp prompt-tag))
(define (mark-parameters-all mps [none-v #f] [prompt-tag (default-continuation-prompt-tag)])
(continuation-mark-set->list* (current-continuation-marks) mps none-v prompt-tag))
(serializable-struct
mark-parameter ()
#:transparent
#:property prop:procedure mark-parameter-first)
(define-syntax with-continuation-mark*
(syntax-rules ()
[(_ () body-expr ...)
(begin body-expr ...)]
[(_ ([k v]) body-expr ...)
(with-continuation-mark k v body-expr ...)]
[(_ ([k0 v0] [k1 v1] ...) body-expr ...)
(with-continuation-mark k0 v0
(with-continuation-mark* ([k1 v1] ...)
body-expr ...))]))
(define-syntax (mark-parameterize stx)
(syntax-case stx ()
[(_ ([mp expr] ...) body-expr ...)
(with-syntax ([(expr-val ...) (generate-temporaries #'(expr ...))])
(syntax/loc stx
(let ([expr-val expr] ...)
(with-continuation-mark* ([mp expr-val] ...)
body-expr ...))))]))
(provide mark-parameterize
(struct-out mark-parameter))
(provide/contract
[mark-parameter-first ((mark-parameter?) (continuation-prompt-tag?) . ->* . any/c)]
[mark-parameter-all ((mark-parameter?) (continuation-prompt-tag?) . ->* . list?)]
[mark-parameters-all (((listof mark-parameter?)) (any/c continuation-prompt-tag?) . ->* . (listof vector?))])