my $string_var = defined( $input_field ) || '';

This will set $string_var either to 1 or to "", no matter what $input_field was set to. Looking at the variable names, this is hardly what you want.

($string_var || '')

This evaluates to "" if $string_var is undef, 0, or "0". You don't want to change "0" or 0 to the empty string, do you?

Why don't you use the defined-or operator //? $string_var//'' evaluates to "" only if $string_var is "" or undef. 0 and "0" are not changed.

Ancient perl versions have no defined-or-operator, so you have to resort to something like $never_undef=defined($perhaps_undef) ? $perhaps_undef : ''; for code that is expected to work with ancient perl verisons.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^2: Undef and Unitialized Issue by afoken
in thread Undef and Unitialized Issue by Pharazon

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