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Postings from December 2001
Bernie Cosell schreef op 05 december 2001:
> On 5 Dec 2001, at 14:09, Eugene van der Pijll wrote:
>
> > Bernie Cosell schreef op 05 december 2001:
> > > Meta-question: since Perl is content to try to *call* '&main::;' is there
> > > some trickery to *DEFINE* such a subroutine? For example, trying:
> > > main:: { die; }
> > > gets you what I would have expected in the '..&' case: a syntax error for a
> > > missing subroutine name.
> >
> > perl -e'*;=sub {1}; print &;'
>
> good heavens.. the actual subroutine name is semi-colon?? So the name isn't
> missing and isn't null, but is ';'. I'm not sure that that doesn't make it
> MORE confusing to me --- Are there other punctuation marks that work in that
> context??
>
> Three questions:
> 1) is semicolon the ONLY puncuation mark that has this odd
> special-dispensation?
I'd expect not.
> 2) WHY does perl allow this --- it still seems like a slam-dunk syntax error
> situation to me
The global variables @a, $a, %a and &a are all stored in the same data
structure (the typeglob, see perldata). Therefore, if the subscript
separator variable $; can be used, there should be an entry in the
symbol table for ;, and @;, %; and &; are valid names.
> 3) who *discovered* this anomaly? [how does someone even think to TRY
> something bizarre like this.....]
In my case, I discovered it quite accidentally. I replaced exit with &f,
resulting in an 'undefined subroutine f called' error. Then Piers said
it could be one character shorter...
Eugene
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