Works for strings too: $x ||= '': will avoid warnings about using an undefined value in a print, string concatenation, string comparison, regular expression, and so on.

That also turns '0' into '' and so would probably be better written as: 

$x= ''  if ! defined $x;

[download]

Or you can use //= if you are on the bleading edge and eschew backward compatability. Note that ||= is probably the best choice for the numeric case as treating '' as a number can also cause a warning.

- tye        

In reply to Re^2: Or, Or, Equals Zero, $x ||= 0 ('') by tye
in thread Or, Or, Equals Zero, $x ||= 0 by Anonymous Monk

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