I tried to recreate your results, but the following code does not behave as you described: 

#! perl

use strict ;
use warnings ;
$|++ ;

my %myhash = () ;
while ( <DATA> )
{
    my ( $key, $value ) = split ;
    push( @{ $myhash{ $key } }, $value ) ;
}

for my $key ( qw/ ni perch shrubbery / )
{
    if ( $myhash{ $key } )
    {
        print "Found $key on pass 1.\n" ;
    }
}

for my $key (  qw/ ni perch shrubbery / )
{
    if ( $myhash{ $key } )
    {
        print "Found $key on pass 2.\n" ;
    }
}

__DATA__
foo 1
bar 2
zoot 3
perl 4

[download]

Could you post some working code that produces the results you mentioned?


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In reply to Re: Presence of Key in Hash of Arrays by DamnDirtyApe
in thread Presence of Key in Hash of Arrays by insensate

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