Re: [PATCH 1/2] srfi-34: Replace the 'raise' core binding.

[Andy Wingo <wingo@igalia.com>]

On Mon 25 Nov 2019 17:45, Ludovic Courtès <ludo@gnu.org> writes:

> In Guile 2.x, (srfi srfi-34) would already replace 'raise'.  Replacing
> avoids a run-time warning about the core binding being overridden.
>
> * module/srfi/srfi-34.scm (raise): New variable.
> Mark it as #:replace instead of #:re-export.
> ---
>  module/srfi/srfi-34.scm | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/module/srfi/srfi-34.scm b/module/srfi/srfi-34.scm
> index 0e7ad995d..255bfecb9 100644
> --- a/module/srfi/srfi-34.scm
> +++ b/module/srfi/srfi-34.scm
> @@ -1,6 +1,6 @@
>  ;;; srfi-34.scm --- Exception handling for programs
>  
> -;; Copyright (C) 2003, 2006, 2008, 2010 Free Software Foundation, Inc.
> +;; Copyright (C) 2003, 2006, 2008, 2010, 2019 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
> @@ -27,12 +27,16 @@
>  ;;; Code:
>  
>  (define-module (srfi srfi-34)
> -  #:re-export (with-exception-handler
> -               (raise-exception . raise))
> +  #:re-export (with-exception-handler)
> +  #:replace (raise)
>    #:export-syntax (guard))
>  
>  (cond-expand-provide (current-module) '(srfi-34))
>  
> +(define (raise exn)
> +  "Raise the given exception, invoking the current exception handler on EXN."
> +  (raise-exception exn))

LGTM but it is better to re-export if possible.  The reason is that
right now the compiler recognizes "throw" and "error" as not falling
through, and this is good for a number of reasons; it would be nice to
extend this to raise-exception.  We should make it possible to re-export
and replace at the same time, IMO.

Andy