for a one time construction I would use 
if (defined $foo and $foo eq 'true') {...}

[download]
but if I needed to code similar tests in several places I would go for: 
sub is_true ($) { defined $_[0] and $_[0] eq 'true' }

if (is_true $foo) {...}
if (is_true $bar) {...}

[download]

In reply to Re: When warnings get in the way by salva
in thread When warnings get in the way by Sprad

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