Subject: bug#15540: Circular module imports vs. #:select (2.0.9)

From: Andy Wingo <[email-masked]>
Date: Tue, 21 Jun 2016 13:08:44 +0200

Yes!

As Ian notes this needs a test case.  Some kind Guixer should fix up
this patch and send to Guile so that it lands before we release 2.0.12,
which should come any day now :-)

Andy

On Sun 06 Oct 2013 21:36, [email-masked] (Ludovic Courtès) writes:

> Consider these two modules:
>
> (define-module (a) #:use-module (b) #:export (from-a))
> (define from-a 1)
>
> and:
>
> (define-module (b) #:use-module ((a) #:select (from-a)) #:export (from-b))
> (define from-b 2)
>
> This fails:
>
> scheme@(guile-user)> ,use(a)
> While executing meta-command:
> ERROR: no binding `from-a' in module (a)
>
> whereas this succeeds (starting from a fresh Guile):
>
> scheme@(guile-user)> ,use(b)
> scheme@(guile-user)> from-b
> $1 = 2
>
> Problem is that ‘define-module*’ processes exports after imports.
>
> What about a patch along these lines:
>
> diff --git a/module/ice-9/boot-9.scm b/module/ice-9/boot-9.scm
> index c825b35..24b8f4c 100644
> --- a/module/ice-9/boot-9.scm
> +++ b/module/ice-9/boot-9.scm
> @@ -2872,11 +2872,8 @@ VALUE."
>                (error "expected list of integers for version"))
>            (set-module-version! module version)
>            (set-module-version! (module-public-interface module) version)))
> -    (let ((imports (resolve-imports imports)))
>      (call-with-deferred-observers
>       (lambda ()
> -         (if (pair? imports)
> -             (module-use-interfaces! module imports))
>         (if (list-of valid-export? exports)
>             (if (pair? exports)
>                 (module-export! module exports))
> @@ -2885,6 +2882,9 @@ VALUE."
>             (if (pair? replacements)
>                 (module-replace! module replacements))
>             (error "expected replacements to be a list of symbols or symbol pairs"))
> +       (let ((imports (resolve-imports module)))
> +         (if (pair? imports)
> +             (module-use-interfaces! module imports)))
>         (if (list-of valid-export? re-exports)
>             (if (pair? re-exports)
>                 (module-re-export! module re-exports))
> @@ -2896,7 +2896,7 @@ VALUE."
>         ;; handlers.
>         (if (pair? duplicates)
>             (let ((handlers (lookup-duplicates-handlers duplicates)))
> -               (set-module-duplicates-handlers! module handlers))))))
> +             (set-module-duplicates-handlers! module handlers)))))
>  
>      (if transformer
>          (if (and (pair? transformer) (list-of symbol? transformer))
>
> Thanks,
> Ludo’.