Time and again I see you changing your posts in retrospect without marking updates.

For the sake of a decent discussion, please be consistent.

Now, I'll split my reply into multiple posts, so lets target my first argument:

Firstly:

your original example was: 

my @a;

$a[1] = undef;
$a[2] = 0;
$a[3] = 7;

[download]

and I replied

> > Your table shows exactly a consistent behavior to exists when used with hashes. Unset values just don't exist.

and here we go

use v5.12;
use warnings;

my (@x,%x);

my $i=1;
for my $v (undef,0,7) {
  $x[$i]=$x{$i}=$v;
  $i++;
}

[download]
--- Index exists?
$i     @x     %x
0          
1     1     1
2     1     1
3     1     1
4

[download]

QED!

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

In reply to Re^6: Using exists to check element in array by LanX
in thread Using exists to check element in array by david

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