there are cases where assigning undef makes sense but generally it's a waste of time (which is not Perl style ;)

Applications are especially when passing "positional" lists or assigning to lists, with "gaps".

i.e. 

($a,undef,$b)=@array;            # ignore second parameter

[download]
or 
 function($a,undef,$b) {..}      # treat second parameter as not suppl
+ied

[download]

The latter is especially necessary if you are checking arguments within the sub for definedness and changing to default values.

UPDATE: An extension of this case is a hash or array element which exists but is not defined!

> Of course I use strictures in all my code!

it's more about use warnings to be warned about undefined variables.

UPDATE:

and please be careful not to return undef to "explicitly" return false.

Subs return lists, so what you are actually doing is returning a one-element list instead of an empty one. I.e. @array=func();

Using a blank return is the same like return (); and won't byte you in list context but in scalar context the variable will be undef anyway.

Cheers Rolf

In reply to Re^3: Perl Style: Is initializing variables considered taboo? by LanX
in thread Perl Style: Is initializing variables considered taboo? by ait

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