If bar() is a complex function, then perhaps it should be the one returning the default value...

If that's not reasonable, then perhaps you need a default wrapper or something... Here's two ideas: 

sub mybar {
   my $t = bar();
   return "default" unless defined $t;
   return $t;
}

sub default {
    my $to_call = shift;
    my $default = shift;
    my $t = to_call->(@_);
    return $default unless defined $t;
    return $t;
}

[download]

Or just do what the others said above (5.10+ only): $x = bar() // "default";

-Paul

In reply to Re: Assignment to a value only if it is defined by jettero
in thread Assignment to a value only if it is defined by voj

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