Don Coyote has asked for the wisdom of the Perl Monks concerning the following question:

hacking on %main::, I printed out keys and values. The $=>*main::$ looked an ideal candidate to test out my uninformed theories about local on. When I asked scalar($main::{$}) though the string of the value of the key was returned rather than a value as I was expecting.

scalar($main::{$}), or scalar($main::{q<$>}) from cli, returned the string *main::$ which is the hash value for *main::$ and not a numeric value as I was expecting.

Is this something to do with the implicit recursiveness of the main hash?

Update: oh its scalar() behaviour. returns the scalar if it is a scalar else returns the number of items if its a list being brought into scalar context. Of course!

  • Comment on scalar(*main::{VALUE}) appears to return a string rather than a value?

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Re: scalar(*main::{VALUE}) appears to return a string rather than a value?
by Anonymous Monk on Nov 11, 2012 at 14:05 UTC

    Is this something to do with the implicit recursiveness of the main hash?

    No, but "stash" is a "stash" :)( I assume a)

    What you got is a typeglob, they store everything $ is 

    $ perl -l -
print for $$,  ${ '::$' },  ${  $main::{ '$' }  };
&{  $main::{ '$'  }  };
__END__
2840
2840
2840
Undefined subroutine &main::$ called at - line 2.

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     $ perl -e " use Data::Dump::Streamer; Dump $main::{ q{$} }; "
$VAR1 = *{'::$'};
*{'::$'} = \4032;

$ perl -e " use Data::Dump; dd $main::{ q{$} }; "
do {
  my $a = *main::$;
  $a = \2104;
  $a;
}

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        ok I think I see this now

        
print qq{caret is the special variable symbol for $^}.$/;

ALTERPIDSYM: {
 
 local $main::{'$'} = q{^};
 my $grapplehook = 'tri';
 print ${'::$'};
 print q{?},$grapplehook;

};

print ${ $main::{'$'} };

exit 0;

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        {local ${$main::{q<$>}=q<Coyote>}=q<heheh>;$^=${main::{q<$>}},$$;print($^);}
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        Thanks for the references Anon :)

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