You can grep through it, but you have an error in how you are accessing the array ref. You need to do it like this: 
if (grep /$_/,  @{$tbl{$i}}  ) {

[download]
Update: Removed square brackets which I didn't see the first time around.

Another problem, though, is that $_ gets assigned to in the grep operation, and that the match operator implicitly operates on $_. Thus, grep /$_/, ... is equivalent to grep { $_ =~ /$_/ } (...) which is probably not what you want. Instead, try this: 

while (my $line = <IN>) {
  ...
  for my $i (...) {
    if (grep /$line/, @{$tbl{$i}}) {
      ...
    }
  }
}

[download]

In reply to Re: greping thru a hash of arrays by pc88mxer
in thread greping thru a hash of arrays by pglenski

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