Re: uninitialized vs. undefined

[Tom Christiansen <tchrist@chthon.perl.com>]

>I've always felt there must be a difference between

>  my @a;	# undefined
>  my @a = ();	# defined but empty

>I was slightly disappointed to find out that 5.005_63 deprecates
>defined(@a) to tell the difference.

But it doesn't do that!

    sub testit {
	my @a;
	my @b = ();

	printf "call #%d:\n", ++$count;

	if (defined @a) { print "\ta is defined\n" } 
	if (defined @b) { print "\tb is defined\n" } 

	$a[0] = $b[0] = "none";
    } 


    testit();
    testit();
    testit();

Produces:

    call #1:
    call #2:
	    a is defined
	    b is defined
    call #3:
	    a is defined
	    b is defined


--tom

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Follow-Ups from:

JVromans@squirrel.nl (Johan Vromans)

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JVromans@squirrel.nl (Johan Vromans)

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