Hello smittypaddler,

Some notes:

  1. Obligatory reference on autovivification: Autovivification: What is it and why do I care? by Uri Guttman
  2. $#{$array} can be written more simply without the braces: $#$array
  3. The CPAN module autovivification can be used to disable this behaviour: 
    use strict;
use warnings;
no  autovivification;

my $array;

warn sprintf 'array is%s defined', defined $array ? '' : ' not';
warn         '$#$array is ',             $#$array;
warn sprintf 'array is%s defined', defined $array ? '' : ' not';

    [download]

    Output:

    13:28 >perl 1999_SoPW.pl
array is not defined at 1999_SoPW.pl line 7.
Can't use an undefined value as an ARRAY reference at 1999_SoPW.pl lin
+e 8.

13:28 >

    [download]

Hope that’s of interest,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: Using $# defines a variable? by Athanasius
in thread Using $# defines a variable? by smittypaddler

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