racket/collects/scheme/require.ss
2009-12-02 23:39:55 +00:00

92 lines
3.8 KiB
Scheme

#lang scheme/base
(require (for-syntax scheme/base scheme/require-transform scheme/list
(only-in unstable/syntax syntax-local-eval))
"require-syntax.ss")
(provide matching-identifiers-in)
(define-syntax matching-identifiers-in
(make-require-transformer
(lambda (stx)
(syntax-case stx ()
[(_ rx spec)
(regexp? (syntax-e #'rx))
(let ([rx (syntax-e #'rx)])
(define-values [imports sources] (expand-import #'spec))
(values (filter (lambda (i)
(regexp-match? rx (symbol->string
(syntax-e (import-local-id i)))))
imports)
sources))]))))
(provide subtract-in)
(define-syntax subtract-in
(make-require-transformer
(lambda (stx)
(syntax-case stx ()
[(_ spec specs ...)
(let* ([subs (map (lambda (spec)
(let-values ([(imports srcs) (expand-import spec)])
imports))
(syntax->list #'(specs ...)))]
[subs (map (lambda (i) (syntax-e (import-local-id i)))
(apply append subs))])
(define-values [imports sources] (expand-import #'spec))
(values (filter (lambda (i)
(not (memq (syntax-e (import-local-id i)) subs)))
imports)
sources))]))))
(provide filtered-in)
(define-syntax filtered-in
(make-require-transformer
(lambda (stx)
(syntax-case stx ()
[(_ proc spec)
(let ([proc (syntax-local-eval #'proc)])
(define-values [imports sources] (expand-import #'spec))
(values
(filter-map
(lambda (i)
(let* ([id (import-local-id i)]
[s1 (symbol->string (syntax-e id))]
[s2 (proc s1)])
(cond [(equal? s1 s2) i]
[(string? s2) (make-import (datum->syntax
id (string->symbol s2) id)
(import-src-sym i)
(import-src-mod-path i)
(import-mode i)
(import-req-mode i)
(import-orig-mode i)
(import-orig-stx i))]
[(not s2) #f]
[else (error 'filtered-in "bad result: ~e" s2)])))
imports)
sources))]))))
(provide path-up)
(define-require-syntax (path-up stx)
(syntax-case stx ()
[(_ path-stx)
(let ([s (syntax-e #'path-stx)]) (and (string? s) (module-path? s)))
(let* ([src (syntax-source stx)]
[dirname (lambda (path)
(let-values ([(dir name dir?) (split-path path)]) dir))]
[srcdir (if (and (path-string? src) (complete-path? src))
(dirname src)
(or (current-load-relative-directory)
(current-directory)))])
(define path (syntax-e #'path-stx))
(unless (complete-path? srcdir) (error 'path-up "internal error"))
(parameterize ([current-directory srcdir])
(let loop ([dir srcdir] [path (string->path path)])
(if (file-exists? path)
(datum->syntax stx (path->string path) stx)
(let ([dir (dirname dir)])
(if dir
(loop dir (build-path 'up path))
(raise-syntax-error 'path-up
"file no found in any parent directory"
stx #'path-stx)))))))]))