http://www.perlmonks.org?node_id=1034178

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Why doesn't the following produce an error??
#!/usr/bin/perl use warnings; use strict; use Data::Dumper; my @h = ( { A => 1, B => undef }, { A => 2, B => 2 }, { A => 2, B => undef }, ); $_->{B} ||= $_{A} foreach @h; # Bug! print Dumper(\@h);