Efraim Flashner <efr...@flashner.co.il> skribis:
> On Sun, Jun 05, 2016 at 10:37:12PM +0200, Ludovic Courtès wrote:
[...]
>> I’ll commit a couple of fixes for bugs I just found and that prevent us
>> from doing:
>>
>> (compile "ls" #:from %bournish-language #:to 'scheme).
(This should be be ‘read-and-compile’, not ‘compile’.)
Done in f82c58539e1f7b9b864e68ea2ab0c6a17c15fbb5. Take a look at
tests/bournish.scm for examples of what is expected.
> From ebce5076177314bfd17a53019b3f6b6888762b01 Mon Sep 17 00:00:00 2001
> From: Efraim Flashner <efr...@flashner.co.il>
> Date: Sun, 22 May 2016 14:56:06 +0300
> Subject: [PATCH] bournish: Add `wc' command.
>
> * guix/build/bournish.scm (file-size, wc-c-command, wc-l-command,
> lines+chars, wc-command, wc-command-implementation): New variables.
> (%commands): Add wc command.
[...]
> +(define* (wc-command-implementation filelist #:optional args)
‘files’, not ‘filelist’.
> + (let ((files (filter (lambda (file)
> + (catch 'system-error
> + (lambda ()
> + (lstat file))
> + (lambda args
> + (let ((errno (system-error-errno args)))
> + (format (current-error-port) "~a: ~a~%"
> + file (strerror errno))
> + #f))))
‘stat’ rather than ‘fstat’.
> + (for-each
> + (lambda (file)
> + (let-values (((lines chars)
> + (call-with-input-file file lines+chars)))
> + (match args
> + (#\l
> + (format #t "~a ~a~%" lines file))
> + (#\c
> + (format #t "~a ~a~%" chars file))
> + (_
> + (format #t "~a ~a ~a~%" lines chars file)))))
> + files)))
OK.
> +(define (wc-command args . rest)
> + (let* ((flags (cond ((string=? args "-l") #\l)
> + ((string=? args "-c") #\c)
> + (else #\nul)))) ; no flags, "args" is a file
I’d rather make it:
(define (wc-commands . args)
(cond ((member "-l" args) …)
((member "-c" args) …)
(else …)))
Instead of the #\nul thing, I think it’d be best to have separate
procedures for -l, -c, and the other case.
> + ((@@ (guix build bournish) wc-command-implementation)
> + (if (char=? flags #\nul) (cons args rest) rest) flags)))
This is still not emitting code. :-) IOW, there should be a quasiquote
here.
You can see that by running:
(use-modules (system base compile) (guix build bournish))
(read-and-compile (open-input-string "wc -l foo")
#:from %bournish-language #:to 'scheme)
This should return something like:
`((@ (guix build bournish) wc-l-command-implementation) '("foo"))
Makes sense? We’re almost done.
Please take a look at
<https://www.gnu.org/software/guix/manual/html_node/Coding-Style.html>
to make the last review super fast. ;-)
Thank you!
Ludo’.
