Re: guile-user Digest, Vol 188, Issue 9

[Alex Sassmannshausen <alex.sassmannshausen@gmail.com>]

Hi Zelphir,

Just as a heads up — this is perhaps a little tangential.  I created the
guile-config package
(https://gitlab.com/a-sassmannshausen/guile-config), which builds on
getopt-long to provide a (IMHO) richer and more sustainable approach to
managing commandline options for a program.

Just figured you might be interested to have a look, as you were curious
about the subject matter.

HTH,

Alex

Zelphir Kaltstahl writes:

> On 08.07.2018 18:00, guile-user-request@gnu.org wrote:
>> ------------------------------
>>
>> Message: 3
>> Date: Sun, 8 Jul 2018 08:44:22 -0700
>> From: Matt Wette <matt.wette@gmail.com>
>> To: guile-user@gnu.org
>> Subject: Re: Parsing command line arguments, predicate error
>> Message-ID: <e9c9c87b-389d-70d1-7afe-13a0b03e168d@gmail.com>
>> Content-Type: text/plain; charset=utf-8; format=flowed
>>
>>
>>
>> On 07/08/2018 04:49 AM, Zelphir Kaltstahl wrote:
>>> Hi!
>>>
>>> I decided to take a look at how one can parse command line arguments in
>>> Guile and was looking for something like argparse in Python. It seems
>>> that (use-modules (ice-9 getopt-long)) does the job, except that I hit
>>> one problem and don't know what the mistake I am making is. It seems to
>>> be connected to the usage of `predicate` in my code.
>> You probably want to use quasi-quote + unquote:
>>  ? `((version ... (predicate ,string-exact-integer?))))
>>
>> I believe the module (srfi srfi-37), args-fold, is now recommended over 
>> getopt-long.
>>
>> Matt
>
> That solved the problem, thank you Matt!
> I was so far quite fond of the way one specifies options with
> getopt-long, but the quasi-quote unquote was not mentioned in the Guile
> docs and feels unnatural. There seems to be no reason for it to force me
> to do that, except that it does not work otherwise. I'll probably look
> into how it is done with SRFI-37, because of this.
>
> Apart from this issue, what are the reasons for SRFI-37 to be
> recommended over getopt-long?