I have a list, and sometimes I want to read-ahead (next element) in the list and compare it to my current element (while the index stays on my current element)

If there's a next element (i.e. I'm not out of bounds) then I'll grab a value. If there's no next element then I'm done.

This works .......... 

my $next_version_key = $ordered_list->[($i+1)]->[0] 
     if( $ordered_list->[($i+1)] );

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but then I thought I'd try ............ 
my $next_version_key = $ordered_list->[($i+1)]->[0] || undef;

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and that added .......... 
[] to @{ $ordered_list }

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which meant my list had grown. The next time round, it added ...... 
 
[
  undef,
  {}
]

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next time round .............. 
[
  ${\$VAR1->[3][0]},
  {}
]

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usw. The same happens if I use ............ 
my $next_version_key = $ordered_list->[($i+1)]->[0] || 0;

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Now, it seems as though $ordered_list->[($i+1)]->[0] is evalutaing to true even though it's out-of-bounds but what strange behaviour!!

Can someone throw some light on that for me? This isn't critical as I'm using ... 

my $next_version_key = $ordered_list->[($i+1)]->[0] 
     if( $ordered_list->[($i+1)] );

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which my prefered way .... I'm just interested in the internals with this prob.

Cheers -Ants

In reply to Array mysteriously growing by AntsPants

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