in reply to Re: Uninitialized Value Error When Interleaving
in thread Uninitialized Value Error When Interleaving

1) I will move the my declaration.
2) Yes @foo is shorter. My code should have read... 
#!/usr/bin/perl
use warnings;
use strict;
my @foo = ( 1 , 3 , 5 , 7 );
my @bar = (0, 2 , 4 , 6 , 8 );
print STDOUT my @foobar = map { $_, shift @foo } @bar;

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I'm assuming that this is my problem, no? I do get the proper result "012345678"...just with a warning.
3) I guess I have a talent for ugly... and warnings :-(

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Re: Re: Re: Uninitialized Value Error When Interleaving
by clintp (Curate) on Jul 03, 2001 at 16:39 UTC
    As for #2...no you don't get the proper results. What you're actually getting is: 012345678undef but of course undef doesn't print. :)

    Watch this. It's your code with two small modifications: 

    use warnings;
use strict;
my @foo = ( 1 , 3 , 5 , 7 );
my @bar = (0, 2 , 4 , 6 , 8 );
my @foobar= map { $_, shift @foo } @bar;
print STDOUT join(',', @foobar);

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    When you run this, notice that the list is going to have a trailing ",". That's because join() knows there's an element after the 8 (undef!) and makes a slot for it. And notice the error changed, its now an uninit value in join.
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[d/l]
      Thank you for the great explanation. I understand the problem.
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