Support integer/real options with better error handling.

This commit is contained in:
Alex Shinn 2015-02-13 19:03:54 +09:00
parent a7877b773b
commit 1f08bd90c1

View file

@ -1,5 +1,5 @@
;; app.scm -- unified option parsing and config
;; Copyright (c) 2012-2013 Alex Shinn. All rights reserved.
;; Copyright (c) 2012-2015 Alex Shinn. All rights reserved.
;; BSD-style license: http://synthcode.com/license.txt
;;> Parses command-line options into a config object.
@ -8,17 +8,33 @@
(define (parse-value type str)
(cond
((not (string? str))
str)
(list str #f))
((and (pair? type) (eq? 'list (car type)))
(map (lambda (x) (parse-value (cadr type) x))
(string-split str #\,)))
(let ((res (map (lambda (x) (parse-value (cadr type) x))
(string-split str #\,))))
(list (map car res) (any string? (map cdr res)))))
(else
(case type
((boolean) (not (member str '("#f" "#false" "#F" "#FALSE"))))
((number) (string->number str))
((symbol) (string->symbol str))
((char) (string-ref str 0))
(else str)))))
((boolean)
(list (not (member str '("#f" "#false" "#F" "#FALSE" "false" "FALSE")))
#f))
((number integer real)
(let ((n (string->number str)))
(cond
((and (eq? type 'integer) (not (integer? n)))
(list n "expected an integer"))
((and (eq? type 'real) (not (real? n)))
(list n "expected a real number"))
(else
(list n #f)))))
((symbol)
(list (string->symbol str) #f))
((char)
(if (not (= 1 (string-length str)))
(list #f "expected a single character")
(list (string-ref str 0) #f)))
(else
(list str #f))))))
(define (lookup-conf-spec conf-spec syms strs)
(let ((sym (car syms))
(str (car strs)))
@ -55,43 +71,44 @@
((and (pair? (cddr x)) (member `(not ,ch) (car (cddr x))))
`(not ,x))
(else (lp (cdr ls))))))))
(define (parse-conf-spec str args)
(let* ((strs (string-split str #\.))
(define (parse-long-option str args fail)
(let* ((str+val (string-split str #\= 2))
(str (car str+val))
(args (if (pair? (cdr str+val)) (cons (cadr str+val) args) args))
(strs (string-split str #\.))
(syms (map string->symbol strs))
(spec (lookup-conf-spec conf-spec syms strs)))
(cond
((not spec)
#f)
((and (pair? spec) (eq? 'not (car spec)))
(cons (cons (append prefix (list (car spec))) #f) args))
((eq? 'boolean (cadr spec))
(cons (cons (append prefix (list (car spec))) #t) args))
((null? args)
(error "missing argument to option " str))
(else
(cons (cons (append prefix syms) (parse-value (cadr spec) (car args)))
(cdr args))))))
(define (parse-long-option str args)
(let* ((str+val (string-split str #\= 2))
(str (car str+val))
(args2 (if (pair? (cdr str+val)) (cons (cadr str+val) args) args)))
(or (parse-conf-spec str args2)
(and (string-prefix? "no-" str)
(let ((res (parse-long-option (substring str 3) args)))
;; check for 'no' prefix on boolean
(if (not (string-prefix? "no" str))
(fail prefix conf-spec (car args) args "unknown option")
(let ((res (parse-long-option (substring str 2) args (lambda args #f))))
(cond
((not res)
#f)
(fail prefix conf-spec (car args) args "unknown option"))
((not (boolean? (cdar res)))
(error "'no-' prefix only valid on boolean options"))
(error "'no' prefix only valid on boolean options"))
(else
`(((,@prefix ,(caar res)) . ,(not (cdar res)))
,@(cdr res)))))))))
(define (parse-short-option str args)
`((,(caar res) . #f) ,@(cdr res)))))))
((and (pair? spec) (eq? 'not (car spec)))
(cons (cons (append prefix (list (car spec))) #f) args))
((and (eq? 'boolean (cadr spec)) (null? (cdr str+val)))
(cons (cons (append prefix (list (car spec))) #t) args))
((null? args)
(fail prefix conf-spec (car args) args "missing argument to option"))
(else
(let ((val+err (parse-value (cadr spec) (car args))))
(if (cadr val+err)
(fail prefix conf-spec (car args) args (cadr val+err))
(cons (cons (append prefix syms) (car val+err))
(cdr args))))))))
(define (parse-short-option str args fail)
(let* ((ch (string-ref str 0))
(x (lookup-short-option ch conf-spec)))
(cond
((not x)
#f)
(fail prefix conf-spec (car args) args "unknown option"))
((and (pair? x) (eq? 'not (car x)))
(cons (cons (append prefix (list (car (cadr x)))) #f)
(if (= 1 (string-length str))
@ -103,17 +120,18 @@
args
(cons (string-append "-" (substring str 1)) args))))
((> (string-length str) 1)
(cons (cons (append prefix (list (car x)))
(parse-value (cadr x) (substring str 1)))
args))
(let ((val+err (parse-value (cadr x) (substring str 1))))
(if (cadr val+err)
(fail prefix conf-spec (car args) args (cadr val+err))
(cons (cons (append prefix (list (car x))) (car val+err))
args))))
((null? args)
(error "missing argument to option " x))
(fail prefix conf-spec (car args) args "missing argument to option"))
(else
(cons (cons (append prefix (list (car x))) (car args)) (cdr args))))))
(or (if (eqv? #\- (string-ref (car args) 1))
(parse-long-option (substring (car args) 2) (cdr args))
(parse-short-option (substring (car args) 1) (cdr args)))
(fail prefix conf-spec (car args) args)))
(if (eqv? #\- (string-ref (car args) 1))
(parse-long-option (substring (car args) 2) (cdr args) fail)
(parse-short-option (substring (car args) 1) (cdr args) fail)))
(define (parse-options prefix conf-spec orig-args fail)
(let lp ((args orig-args)
@ -138,9 +156,9 @@
(else (reverse (cdr (reverse prefix))))))
(let ((fail (if (pair? o)
(car o)
(lambda (prefix spec opt args)
;; TODO: search for closest option
(error "unknown option: " opt)))))
(lambda (prefix spec opt args reason)
;; TODO: search for closest option in "unknown" case
(error reason opt)))))
(cond
((null? spec)
(error "no procedure in application spec"))
@ -149,7 +167,7 @@
((@)
(let* ((new-opt-spec (cadr (car spec)))
(new-fail
(lambda (new-prefix new-spec opt args)
(lambda (new-prefix new-spec opt args reason)
(parse-option (prev-prefix prefix) opt-spec args fail)))
(cfg+args (parse-options prefix new-opt-spec args new-fail))
(config (conf-append (car cfg+args) config))