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perl - How can I list all variables that are in a given scope?

I know I can list all of the package and lexcial variables in a given scope using Padwalker's peek_our and peek_my, but how can I get the names and values of all of the global variables like $" and $/?

#!/usr/bin/perl

use strict;
use warnings;

use PadWalker qw/peek_our peek_my/;
use Data::Dumper;

our $foo = 1;
our $bar = 2;

{
    my $foo = 3;
    print Dumper in_scope_variables();
}

print Dumper in_scope_variables();

sub in_scope_variables {
    my %in_scope = %{peek_our(1)};
    my $lexical  = peek_my(1);
    #lexicals hide package variables
    while (my ($var, $ref) = each %$lexical) {
        $in_scope{$var} = $ref;
    }
    ##############################################
    #FIXME: need to add globals to %in_scope here#
    ##############################################
    return \%in_scope;
}
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1 Answer

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You can access the symbol table, check out p. 293 of "Programming Perl" Also look at "Mastering Perl: http://www252.pair.com/comdog/mastering_perl/ Specifically: http://www252.pair.com/comdog/mastering_perl/Chapters/08.symbol_tables.html

Those variables you are looking for will be under the main namespace

A quick Google search gave me:

{
    no strict 'refs';

    foreach my $entry ( keys %main:: )
    {
        print "$entry
";
    }
}

You can also do

*sym = $main::{"/"}

and likewise for other values

If you want to find the type of the symbol you can do (from mastering perl):

foreach my $entry ( keys %main:: )
{
    print "-" x 30, "Name: $entry
";

    print "scalar is defined
" if defined ${$entry};
    print "array  is defined
" if defined @{$entry};
    print "hash   is defined
" if defined %{$entry};
    print "sub    is defined
" if defined &{$entry};
}

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