Hi! i'm relatively new to perl and keep getting this warning:

Use of uninitialized value in string eq at test.pl line 40.

foreach my $key (@keys) {
if (($key->{'att'}->{'for'} eq 'node') && ($key->{'att'}->{'yfiles.type'} eq 'nodegraphics')){ #line 40 here
$nodeD = $key->{'att'}->{'id'};
} elsif (($key->{'att'}->{'for'} eq 'edge') && ($key->{'att'}->{'yfiles.type'} eq 'edgegraphics')){
$edgeD = $key->{'att'}->{'id'};
}
}
i wonder if it is the period in the 'yfiles.type' that is causing the warning and how i can get rid of it?

In reply to period in strings by kc

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