in reply to What is %:: used for?

If you have a module and want to put subs or vars in main, you can use export.
How do you think export does it? By direct symbol table access, accessing things like %:: and %CGI:: and so on!

If you're merely watching the play, don't wander around backstage, please. {grin}

-- Randal L. Schwartz, Perl hacker

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Re: •Re: What is %:: used for?
by Juerd (Abbot) on Jun 14, 2002 at 13:55 UTC

    How do you think export does it? By direct symbol table access, accessing things like %:: and %CGI:: and so on!

    While Exporter does access the symbol table directly by using typeglobs, it doesn't use any hash ending in ::. This is probably because it exports symbols, not symbol tables.

    I searched both Exporter.pm and Exporter::Heavy.pm. The only reference to something ending in :: was: 

            Carp::croak("$_[0]Illegal null symbol in \@${1}::EXPORT")
            if $_[0] =~ /^Unable to create sub named "(.*?)::"/;

    [download]
    in Exporter/Heavy.pm. 

    - Yes, I reinvent wheels.
- Spam: Visit eurotraQ.

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[d/l]
Re: •Re: What is %:: used for?
by SarahM (Monk) on Jun 14, 2002 at 12:51 UTC
    Is export written in perl? I would have thought that export was written in the c code that makes up perl! But if export is written in perl, I can definitely see the use of %::.
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      Yes it's in Perl! See perldoc -m Exporter, but don't stare at it too hard before you're ready to understand and respect the smoke and mirrors revealed.

      -- Randal L. Schwartz, Perl hacker

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        Thanks, it's definitely more complex then anything I've written...but it's not that bad to follow, you just need to understand typeglobs and the system table structure.
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Re: •Re: What is %:: used for?
by cybear (Monk) on Jun 14, 2002 at 14:28 UTC
    If you're merely watching the play, don't wander around backstage, please. {grin}

    Uncalled for... Bad form, old boy.

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      Which part of "{grin}" don't you understand?
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        Bareword "grin" not allowed while "strict subs"
[reply]
        Its use to play down an otherwise condescending and unnecessary statement, perhaps?
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