And this is part of where perl6 will be very nice. It is an important thing though to provide default values especially for web programming since if you port to mod_perl then you are required to provide default values regardless.

 # Provide an empty string as  the default value if the
 # menu item value isn't provided.
 my $menu_item =  param('menu_item')
               // '';
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In perl5 I write this as:

 # Provide an empty string as  the default value if the
 # menu item value isn't provided.
 my $menu_item = param('menu_item');
    $menu_item = '' unless defined $menu_item;

 # OR to be brief
 local $_; # As you enter the block

 $_ = param('menu_item');
 my $menu_item = defined() ? $_ : '';
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Or if you feel like being cute (and slightly obfuscatory)

 $menu_item = defined() ? $_ : '' for (param('menu_item');
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I think you also meant to write unless ! as if but that's separate.

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