sunterlib/s48/args-fold/args-fold.scm

214 lines
9.6 KiB
Scheme

;;; args-fold.scm - a program argument processor
;;;
;;; Copyright (c) 2002 Anthony Carrico
;;;
;;; All rights reserved.
;;;
;;; Redistribution and use in source and binary forms, with or without
;;; modification, are permitted provided that the following conditions
;;; are met:
;;; 1. Redistributions of source code must retain the above copyright
;;; notice, this list of conditions and the following disclaimer.
;;; 2. Redistributions in binary form must reproduce the above copyright
;;; notice, this list of conditions and the following disclaimer in the
;;; documentation and/or other materials provided with the distribution.
;;; 3. The name of the authors may not be used to endorse or promote products
;;; derived from this software without specific prior written permission.
;;;
;;; THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
;;; IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
;;; OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
;;; IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
;;; INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
;;; NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
;;; DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
;;; THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
;;; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
;;; THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
(define option #f)
(define option-names #f)
(define option-required-arg? #f)
(define option-optional-arg? #f)
(define option-processor #f)
(define option? #f)
(let ()
(define-record-type option-type
($option names required-arg? optional-arg? processor)
$option?
(names $option-names)
(required-arg? $option-required-arg?)
(optional-arg? $option-optional-arg?)
(processor $option-processor))
(set! option $option)
(set! option-names $option-names)
(set! option-required-arg? $option-required-arg?)
(set! option-optional-arg? $option-optional-arg?)
(set! option-processor $option-processor)
(set! option? $option?))
(define args-fold
(lambda (args
options
unrecognized-option-proc
operand-proc
. seeds)
(letrec
((find
(lambda (l ?)
(cond ((null? l) #f)
((? (car l)) (car l))
(else (find (cdr l) ?)))))
(find-option
;; ISSUE: This is a brute force search. Could use a table.
(lambda (name)
(find
options
(lambda (option)
(find
(option-names option)
(lambda (test-name)
(equal? name test-name)))))))
(scan-short-options
(lambda (index shorts args seeds)
(if (= index (string-length shorts))
(scan-args args seeds)
(let* ((name (string-ref shorts index))
(option (or (find-option name)
(option (list name)
#f
#f
unrecognized-option-proc))))
(cond ((and (< (+ index 1) (string-length shorts))
(or (option-required-arg? option)
(option-optional-arg? option)))
(let-values
((seeds (apply (option-processor option)
option
name
(substring
shorts
(+ index 1)
(string-length shorts))
seeds)))
(scan-args args seeds)))
((and (option-required-arg? option)
(pair? args))
(let-values
((seeds (apply (option-processor option)
option
name
(car args)
seeds)))
(scan-args (cdr args) seeds)))
(else
(let-values
((seeds (apply (option-processor option)
option
name
#f
seeds)))
(scan-short-options
(+ index 1)
shorts
args
seeds))))))))
(scan-operands
(lambda (operands seeds)
(if (null? operands)
(apply values seeds)
(let-values ((seeds (apply operand-proc
(car operands)
seeds)))
(scan-operands (cdr operands) seeds)))))
(scan-args
(lambda (args seeds)
(if (null? args)
(apply values seeds)
(let ((arg (car args))
(args (cdr args)))
;; NOTE: This string matching code would be simpler
;; using a regular expression matcher.
(cond
(;; (rx bos "--" eos)
(string=? "--" arg)
;; End option scanning:
(scan-operands args seeds))
(;;(rx bos
;; "--"
;; (submatch (+ (~ "=")))
;; "="
;; (submatch (* any)))
(and (> (string-length arg) 4)
(char=? #\- (string-ref arg 0))
(char=? #\- (string-ref arg 1))
(not (char=? #\= (string-ref arg 2)))
(let loop ((index 3))
(cond ((= index (string-length arg))
#f)
((char=? #\= (string-ref arg index))
index)
(else
(loop (+ 1 index))))))
;; Found long option with arg:
=> (lambda (=-index)
(let*-values
(((name)
(substring arg 2 =-index))
((option-arg)
(substring arg
(+ =-index 1)
(string-length arg)))
((option)
(or (find-option name)
(option (list name)
#t
#f
unrecognized-option-proc)))
(seeds
(apply (option-processor option)
option
name
option-arg
seeds)))
(scan-args args seeds))))
(;;(rx bos "--" (submatch (+ any)))
(and (> (string-length arg) 3)
(char=? #\- (string-ref arg 0))
(char=? #\- (string-ref arg 1)))
;; Found long option:
(let* ((name (substring arg 2 (string-length arg)))
(option (or (find-option name)
(option
(list name)
#f
#f
unrecognized-option-proc))))
(if (and (option-required-arg? option)
(pair? args))
(let-values
((seeds (apply (option-processor option)
option
name
(car args)
seeds)))
(scan-args (cdr args) seeds))
(let-values
((seeds (apply (option-processor option)
option
name
#f
seeds)))
(scan-args args seeds)))))
(;; (rx bos "-" (submatch (+ any)))
(and (> (string-length arg) 1)
(char=? #\- (string-ref arg 0)))
;; Found short options
(let ((shorts (substring arg 1 (string-length arg))))
(scan-short-options 0 shorts args seeds)))
(else
(let-values ((seeds (apply operand-proc arg seeds)))
(scan-args args seeds)))))))))
(scan-args args seeds))))