## no warnings or errors $ perl -e "print @{ undef() }; print 6" 6 ## a warning is issued, but 6 still gets printed $ perl -we "print @{ undef() } Use of uninitialized value in array dereference at -e line 1. 6 ## with strict the warning is fatal, 6 not printed cause program died $ perl -Mstrict -we "print @{ undef() } Can't use an undefined value as an ARRAY reference at -e line 1.