I'm not quite sure what is going on here. Showing a bit more code would be helpful as to the overall objective. 
foreach my $string ( @word ) {
      if ( $uword{ $string }[ 0 ] == 1 ) {
         push @{ $uword{ $string } }, $line;
         next;
      }
      $uword{ $string }[ 0 ] = 1;
      push @{ $uword{ $string } }, $line;
   }


#this [0] is apparently not needed
#maybe I'm missing something, but what do you think
#that this does?
#simplify to just...

foreach my $string (@word)
{
   push ( @{$uword{$string}}, $line );
}

[download]
Now, 
@{ $uword{ $seen{ $key }[ 1 ] }
# there is no closing curly for the @
# its rather strange looking but
# { $seen{ $key }[ 1 ] } is the key for the hash

[download]
You've got some pretty complex syntax and maybe if you explained a bit more, some major simplifications could be made.

You are adding an unnecessary complication with this [0] =1 or not stuff. It is not necessary. 

push @{$hash{$key}}, $value;

[download]
is all you need. If $hash{$key} doesn't exist prior to the push, the key will be created automatically.

In reply to Re: error joining hashref of an arrayref by Marshall
in thread error joining hashref of an arrayref by ag4ve

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