in use strict; the behavior of push is predictable, but without -- and using a string in $a[0] -- the behavior is not predictable
Wrong. The behaviour is perfectly predictable. Observe 
use Data::Dumper;
@a = 'bar';
@bar = 6;
warn push @{$a[0]}, 7;
warn Dumper( \@a, \@bar );

warn push @{"$a[0]"}, 8;
warn Dumper( \@a, \@bar );

warn push @{"bar"}, 9;
warn Dumper( \@a, \@bar );
undef $a[0];
warn push @{$a[0]}, 11;
warn Dumper( \@a, \@bar );
__END__
2 at - line 4.
$VAR1 = [
          'bar'
        ];
$VAR2 = [
          6,
          7
        ];
3 at - line 7.
$VAR1 = [
          'bar'
        ];
$VAR2 = [
          6,
          7,
          8
        ];
4 at - line 10.
$VAR1 = [
          'bar'
        ];
$VAR2 = [
          6,
          7,
          8,
          9
        ];
1 at - line 13.
$VAR1 = [
          [
            11
          ]
        ];
$VAR2 = [
          6,
          7,
          8,
          9
        ];

[download]

without perl may use the @{$something} as array-ref or variable name... a bit confusing, doesn't it?
Why? Observe 
@a = 'bar';
@bar = 6;

warn 'PUSHING ONTO @BAR' if defined $a[0];

push @{$a[0]}, 'bar';

undef $a[0];

warn 'PUSHING ONTO $a[0]' if not defined $a[0];

push @{$a[0]}, 'bar';

use Data::Dumper;
warn Dumper( \@a, \@bar );

__END__
PUSHING ONTO @BAR at - line 4.
PUSHING ONTO $a[0] at - line 10.
$VAR1 = [
          [
            'bar'
          ]
        ];
$VAR2 = [
          6,
          'bar'
        ];

[download]

In reply to Re: Re: Re: push undefined and vivification by Anonymous Monk
in thread push undefined and vivification by oha

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