package Bob;

my $thingy = {One => 1, Two => 2};

sub doit {
    my $key = '{One}';
    eval "print \"thingy one is \$thingy->$key\n\"";
    #my $x = $thingy;
}

1;

##</code><code>##

#!/usr/local/bin/perl

use strict;
use warnings;
use Bob;
Bob->doit();

##</code><code>##

Use of uninitialized value in concatenation (.) or string at (eval 1) line 1.
thingy one is

##</code><code>##

thingy one is 1