Subject: bug#67255: define-library does not support 'rename' directives

From: Maxim Cournoyer <[email-masked]>
Date: Wed, 22 Nov 2023 22:57:32 -0500

Hello!

Timothy Sample <[email-masked]> writes:

> Timothy Sample <[email-masked]> writes:
>
>> Maxim Cournoyer <[email-masked]> writes:
>>
>>> Our R7RS define-library syntax, from (ice-9 r7rs-library) does not
>>> support renaming bindings to export, via 'rename' directives.
>>
>> I appreciate your R7RS debugging effort.  Thanks!
>
> Actions speak louder than words, so here’s a patch!
>
> The ‘define-library’ syntax uses the R6RS ‘library’ syntax under the
> hood.  TIL that R6RS and R7RS have different syntax for 'rename'.  In
> R6RS, you write:
>
>     (export (rename (internal external)))
>
> while in R7RS, it’s:
>
>     (export (rename internal external))
>
> My patch adds a conversion step to deal with this difference.

Oh, excellent, thank you!

>>>From b87bf8910ac8e75dc0ec63cb7385ddf199fd400c Mon Sep 17 00:00:00 2001
> From: Timothy Sample <[email-masked]>
> Date: Mon, 20 Nov 2023 11:01:08 -0600
> Subject: [PATCH] Use R7RS 'rename' syntax for exports.
>
> Fixes <https://bugs.gnu.org/67255>.
> Reported by Maxim Cournoyer <[email-masked]>.

Nitpick: at least 'Reported-by' is a common git trailer, and these
must appear at the bottom of the git commit.

> * module/ice-9/r7rs-libraries.scm (define-library): Convert R7RS
> exports to R6RS exports before passing them on to 'library'.
> ---
>  module/ice-9/r7rs-libraries.scm | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/module/ice-9/r7rs-libraries.scm b/module/ice-9/r7rs-libraries.scm
> index 63a300a26..f8b6b4c59 100644
> --- a/module/ice-9/r7rs-libraries.scm
> +++ b/module/ice-9/r7rs-libraries.scm
> @@ -1,5 +1,5 @@
>  ;; R7RS library support
> -;;      Copyright (C) 2020, 2021 Free Software Foundation, Inc.
> +;;      Copyright (C) 2020, 2021, 2023 Free Software Foundation, Inc.
>  ;;
>  ;; This library is free software; you can redistribute it and/or
>  ;; modify it under the terms of the GNU Lesser General Public
> @@ -97,12 +97,17 @@
>             ((decl ...)
>              (partition-decls #'(decl ... . decls) exports imports code))))))
>  
> +    (define (r7rs-export->r6rs-export export)
> +      (syntax-case export (rename)
> +        ((rename internal external) #'(rename (internal external)))
> +        (_ export)))
> +
>      (syntax-case stx ()
>        ((_ name decl ...)
>         (call-with-values (lambda ()
>                             (partition-decls #'(decl ...) '() '() '()))
>           (lambda (exports imports code)
>             #`(library name
> -               (export . #,exports)
> +               (export . #,(map r7rs-export->r6rs-export exports))
>                 (import . #,imports)
>                 . #,code)))))))

It at least works for my use case (SRFI 128), so it's for sure an
improvement :-).  You can see it in action in the series I've sent today.

-- 
Thanks,
Maxim