if a variable is empty and has only spaces

Strictly speaking a variable can be empty (value is undef) or contains only spaces:
if (defined $var or $var =~ /^\s+$/) {
    # $var is empty or contains only whitespace
}

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The \s actually tests for any white-space character, including tabs and new-lines.

In reply to Re: Regular Expression Help! by cdarke
in thread Regular Expression Help! by Anonymous Monk

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