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3.2.180 undefundef This function undefines the value of The function always returns the undefined value.
This is useful because you can omit the undef $foo; undef $bar{'blurfl'}; undef @ary; undef %assoc; undef &mysub; Without an argument, undef is just used for its value: return (wantarray ? () : undef) if $they_blew_it; select(undef, undef, undef, $naptime); You may use undef as a placeholder on the left side of a list assignment, in which case the corresponding value from the right side is simply discarded. Apart from that, you may not use undef as an lvalue. |