[debbugs-tracker] bug#9776: closed (case-lambda should accept zero clauses)

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Your message dated Sat, 09 Mar 2013 11:17:44 +0100
with message-id <address@hidden>
and subject line Re: bug#9776: case-lambda should accept zero clauses
has caused the debbugs.gnu.org bug report #9776,
regarding case-lambda should accept zero clauses
to be marked as done.

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9776: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=9776
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> --- Begin Message ---
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> Subject: 
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> case-lambda should accept zero clauses
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> Date: 
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> Mon, 17 Oct 2011 12:15:40 +0200
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> User-agent: 
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> Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux)
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> Hello guilers,
>
> the case-lambda form is specified in r6rs-lib as accepting any number of
> clauses, including zero. So this should not give an error:
>
> scheme@(guile-user)> (case-lambda)
> While compiling expression:
> ERROR: Syntax error:
> standard input:1:0: case-lambda: bad case-lambda in form (case-lambda)
>
> Instead it should return a procedure that never gets the right number of
> arguments.
>
> Regards,
>
> -- 
> Göran Weinholt <address@hidden>
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> --- End Message ---
> --- Begin Message ---
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> Subject: 
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> Re: bug#9776: case-lambda should accept zero clauses
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> Date: 
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> Sat, 09 Mar 2013 11:17:44 +0100
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> User-agent: 
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> Gnus/5.13 (Gnus v5.13) Emacs/24.2 (gnu/linux)
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> On Sat 02 Mar 2013 19:13, Andy Wingo <address@hidden> writes:
>
> > Picking up an old thread.  What do people think about the attached
> > patch?  It preserves arity checking for case-lambdas defined in the same
> > compilation unit.  Case-lambdas are converted to nullary procedures in
> > the last minute, before compiling or memoizing.  Calling one of these
> > procedures with arguments will still produce an arity-check warning;
> > calling one without arguments will not.  In both cases a
> > wrong-number-of-args exception is thrown at runtime (either by the
> > normal argument count check or via the explicit throw in the body).
> >
> > I think allowing lambda-body to be #f is the right way to go because it
> > precludes inlining of ((case-lambda)).
> >
> > I'll push soon if there are no comments.
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> Pushed.  Later we can figure out a way to warn for all applications of
> (case-lambda), regardless of arity.
>
> Andy
> -- 
> http://wingolog.org/
>
>
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