This is very simple, but it happens often and I have to write extra code to handle it :
use Data::Dumper;
my $hashref;
print Dumper $hashref;
if(exists $hashref->{a}->{b})
{
# Do something
}
print Dumper($hashref);
Of course, at the first print $hashref is undef, but after the exists statement $hashref is now:
{
'a' => {}
}
Why ?
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