racket/collects/help/help-utils.ss
2009-09-13 15:33:24 +00:00

84 lines
3.0 KiB
Scheme

#lang scheme/base
;; This file provides the utilities that mzscheme's `help' form uses.
;; It is required dynamically when used from mzscheme, to avoid the
;; loading overhead, and to have mzscheme independent of having the
;; documentation system.
(require setup/xref
scribble/xref
scribble/manual-struct
net/uri-codec
net/sendurl
scheme/path
scheme/list
"search.ss")
(provide search-for find-help find-help/lib go-to-main-page)
(define (search-for strs)
(perform-search (apply string-append (add-between strs " "))))
(define-namespace-anchor anchor)
(define (find-help/lib sym lib)
(let ([id (parameterize ([current-namespace
(namespace-anchor->empty-namespace anchor)])
(namespace-require `(for-label ,lib))
(namespace-syntax-introduce (datum->syntax #f sym)))])
(if (identifier-label-binding id)
(find-help id)
(error 'help "no binding for identifier: ~a from module: ~a" sym lib))))
(define (find-help id)
(let* ([lb (identifier-label-binding id)]
[b (and (not lb) (identifier-binding id))]
[any-b (or lb b)]
[b (and (not (eq? 'lexical any-b)) any-b)]
[xref (load-collections-xref
(lambda ()
(printf "Loading help index...\n")))])
(if b
(let ([tag (xref-binding->definition-tag xref b (if lb #f 0))])
(if tag
(go-to-tag xref tag)
(error 'help
"no documentation found for: ~e provided by: ~a"
(syntax-e id)
(module-path-index-resolve (caddr b)))))
(search-for-exports xref (syntax-e id) any-b))))
(define (search-for-exports xref sym binding)
(let ([idx (xref-index xref)]
[libs null])
(for ([entry (in-list idx)])
(when (and (exported-index-desc? (entry-desc entry))
(eq? sym (exported-index-desc-name (entry-desc entry))))
(set! libs (append libs (exported-index-desc-from-libs
(entry-desc entry))))))
(if (null? libs)
(printf "Not found in any library's documentation: ~a\n" sym)
(begin
(printf "~a, but provided by:\n"
(if binding
"No documentation available for binding"
"No current binding"))
(let loop ([libs libs])
(unless (null? libs)
(unless (member (car libs) (cdr libs))
(printf " ~a\n" (car libs)))
(loop (cdr libs))))))))
(define (report-sending-browser file)
(printf "Sending to web browser...\n file: ~a\n" file))
(define (go-to-main-page)
(send-main-page #:notify report-sending-browser))
(define (go-to-tag xref t)
(let-values ([(file anchor) (xref-tag->path+anchor xref t)])
(report-sending-browser file)
(when anchor (printf " anchor: ~a\n" anchor))
(unless (send-url/file file #:fragment (and anchor (uri-encode anchor)))
(error 'help "browser launch failed"))))