Monks, I have a situation that I cannot seem to get around. I am using "exists" on a hash and I keep getting the following error:

exists argument is not a HASH or ARRAY element or a subroutine at deploy.pl line 166 (#1) (F) The argument to exists() must be a hash or array element or a subroutine with an ampersand, such as: $foo{$bar} $ref->{"susie"}12 &do_something Uncaught exception from user code: exists argument is not a HASH or ARRAY element or a subroutine at deploy .pl line 166. at deploy.pl line 166

Here is the code:</> 

use strict;
use warnings;
use File::Find;

my %old_list=();
  my %new_list=();
  my $diffs=DirCompare();
  print "$_\n" for @$diffs;

  find ( sub { $old_list { $_ } = 1 }, $ARCHIVE );    
  find ( sub { $new_list { $_ } = 1 }, $SourceDir ); 

sub DirCompare{
  
  for my $file ( keys %old_list ) {
    if ( exists %new_list{$file} ) {
       next;
     }
    else {
      push @diffs, "Old file not in new: $file";
    }
  }
  
  for my $file ( keys %new_list) {
    if ( exists %old_list{ $file } ) {
      next;
    }
    else {
      push @diffs, "Old file not in new: $file";
    }
  }
  

  return \@diffs;
}

[download]

Any light that you can shed on this issue would be greatly appreciated.

In reply to exists EXPR error by smturner1

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