Hi,

When I let a sub return a reference to a not existing element in a hashref in a hashref, perl yields the "Use of uninitialized value" warning.
However, I would expect it to be created automatically.


#!/usr/bin/perl -wl
use strict;

my $hashref = { foo => { bar => 'xyzzy' } };

sub name_me {
    # Note: there is no $hashref->{foo}{foo}
    return \ $hashref->{foo}{foo};
}

print ${ name_me() };

# Note: I narrowed it down to this code. The original code
# was about 50 lines. Because this is just a fragment, I couldn't
# think of a proper name for the sub. Sorry :)

[download]

The weird thing is, that if i put the hashref in the dereference, or if i have a single-layered $hashref, it doesn't show the warning. Why is perl showing a warning with the above script? 

2;0 juerd@ouranos:~$ perl -e'undef christmas'
Segmentation fault
2;139 juerd@ouranos:~$

[download]

In reply to Autovivification not working? by Juerd

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