Subject: bug#21698: accessing multiple flagged values with (ice-9 getopt-long)

From: Matt Wette <[email-masked]>
Date: Fri, 24 Jun 2016 08:21:11 -0700

Thanks for the pointer.  I can work with SRFI-37.  I am OK w/ rejection of the patch.  — Matt

> On Jun 24, 2016, at 7:53 AM, Andy Wingo <[email-masked]> wrote:
> 
> Hi Matt,
> 
> Thanks for the patch.  My instinct however is to point you towards
> SRFI-37, which in addition to supporting multiple argument values can
> also be used to fold over the precise argument order.  I just don't know
> that we should be expanding (ice-9 getopt-long); it has its use case and
> if your needs go beyond it, then probably your needs go way beyond it.
> 
>  https://www.gnu.org/software/guile/manual/html_node/SRFI_002d37.html
> 
> Ludovic, second opinions?
> 
> Andy
> 
> On Sat 17 Oct 2015 19:05, Matt Wette <[email-masked]> writes:
> 
>> This is in reference to guile-2.0.11.
>> 
>> The (ice-9 getopt-long) module does not provide a process for
>> accessing multiple command line arguments.
>> 
>> A patch for ice-9/getopt-long.scm is attached which adds the procedure
>> getopt-ref/many to access multiple argument values.
>> 
>> The following program and results illustrate the use of the current
>> getopt-ref and the proposed getopt-ref/many:
>> 
>> mwette$ ./gotest.scm -f foo1 -b bar1 -f foo2 baz1 baz2
>> 
>> program arguments:
>> 
>> ("./gotest.scm" "-f" "foo1" "-b" "bar1" "-f" "foo2" "baz1" "baz2")
>> 
>> getopt using option-ref:
>> 
>> foo: "foo2"
>> 
>> bar: "bar1"
>> 
>> getopt using option-ref/many:
>> 
>> foo: ("foo1" "foo2")
>> 
>> bar: "bar1"
>> 
>> where
>> 
>> mwette$ cat gotest.scm 
>> 
>> #!/opt/local/bin/guile
>> 
>> !#
>> 
>> (use-modules (ice-9 getopt-long))
>> 
>> (define spec
>> 
>> '((foo (single-char #\f) (value #t))
>> 
>> (bar (single-char #\b) (value #t))))
>> 
>> (let* ((args (program-arguments))
>> 
>> (opts (getopt-long args spec)))
>> 
>> (simple-format #t "program arguments:\n")
>> 
>> (simple-format #t "~S\n" args)
>> 
>> (simple-format #t "\ngetopt using option-ref:\n")
>> 
>> (simple-format #t "foo: ~S\n" (option-ref opts 'foo #f))
>> 
>> (simple-format #t "bar: ~S\n" (option-ref opts 'bar #f))
>> 
>> (simple-format #t "\ngetopt using option-ref/many:\n")
>> 
>> (simple-format #t "foo: ~S\n" (option-ref/many opts 'foo #f))
>> 
>> (simple-format #t "bar: ~S\n" (option-ref/many opts 'bar #f))
>> 
>> )
>> 
>> 
>> 
>> *** getopt-long.scm-orig	2015-10-15 06:40:29.000000000 -0700
>> --- getopt-long.scm	2015-10-17 09:42:41.000000000 -0700
>> ***************
>> *** 154,159 ****
>> --- 154,173 ----
>>  ;;; (option-ref (getopt-long ...) 'x-includes 42) => "/usr/include"
>>  ;;; (option-ref (getopt-long ...) 'not-a-key! 31) => 31
>> 
>> + ;;; (option-ref/many OPTIONS KEY DEFAULT)
>> + ;;; Return value in alist OPTIONS using KEY, a symbol; or DEFAULT if not
>> + ;;; found.  If multiple arg-options provided a list is returned.  The value
>> + ;;; is either a string, a list or `#t'.
>> + ;;;
>> + ;;; For example, if the above was executed with multiple x-includes flags,
>> + ;;; then all will be returned in a list:
>> + ;;;
>> + ;;; (getopt-long '("my-prog" "-vk" "/tmp" "foo1" "--x-includes=/usr/include"
>> + ;;;                "--x-includes=/opt/includd" "--" "-fred" "foo2" "foo3")
>> + ;;;                grammar)
>> + ;;; (option-ref/many (getopt-long ...) 'x-includes 42)
>> + ;;; => ("/usr/include" "/opt/include")
>> + 
>>  ;;; Code:
>> 
>>  (define-module (ice-9 getopt-long)
>> ***************
>> *** 162,168 ****
>>    #:use-module (ice-9 match)
>>    #:use-module (ice-9 regex)
>>    #:use-module (ice-9 optargs)
>> !   #:export (getopt-long option-ref))
>> 
>>  (define %program-name (make-fluid "guile"))
>>  (define (program-name)
>> --- 176,182 ----
>>    #:use-module (ice-9 match)
>>    #:use-module (ice-9 regex)
>>    #:use-module (ice-9 optargs)
>> !   #:export (getopt-long option-ref option-ref/many))
>> 
>>  (define %program-name (make-fluid "guile"))
>>  (define (program-name)
>> ***************
>> *** 368,371 ****
>> --- 382,397 ----
>>  The value is either a string or `#t'."
>>    (or (assq-ref options key) default))
>> 
>> + (define (option-ref/many options key default)
>> +   "Return value, or values, in alist OPTIONS using KEY, a symbol; or DEFAULT if not found.
>> + The value is either a string, a list or `#t'."
>> +   (let loop ((rez #f) (opts options))
>> +     (if (null? opts) (or rez default)
>> + 	(if (eq? key (caar opts))
>> + 	    (cond
>> + 	     ((pair? rez) (loop (cons (cdar opts) res) (cdr opts)))
>> + 	     (rez (loop (list (cdar opts) rez) (cdr opts)))
>> + 	     (else (loop (cdar opts) (cdr opts))))
>> + 	    (loop rez (cdr opts))))))
>> + 
>>  ;;; getopt-long.scm ends here