Use a regular expression: 

if ($var =~ /^\s*$/) {
   # do something
}

[download]

The regex means "if $var consists of nothing but 0 or more spaces between the beginning and the end ..." (for more on that, type perldoc perlre on your system)

Beware : defined has a meaning in Perl.

Philosophy can be made out of anything. Or less -- Jerry A. Fodor

In reply to Re: Handling undefined string content by arturo
in thread Handling undefined string content by akm2

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