Here’s how to do what you want to do: 
use strict;
use warnings;
use Data::Dump;

{
    my %toys = ( frisbee => 5 );

    dd \%toys;
    play_around(\%toys);
    dd \%toys;
}

sub play_around {
    die "expected one arg"  unless @_ == 1;
    die "expected hash arg" unless ref($_[0]) eq "HASH";
    our %t; local *t = $_[0];
    $t{leggo} = "yes";
}

[download]
When run, that prints out: 
{ frisbee => 5 }
{ frisbee => 5, leggo => "yes" }

[download]
See? Nice and easy!

In reply to Re: passing of variables by tchrist
in thread passing of variables by itsscott

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