#!/usr/bin/perl
use strict;
use warnings;


die "No search terms supplied!" unless @ARGV;
my @words = @ARGV;

my $regex =    join("|",@words)  ;
my $expr = qr /^($regex)$/;

$/ = ' ';
my $i = 0;
my $words = {};
my $pos = tell(DATA);
for my $word (<DATA>)
{
    chomp $word;
    $i++;
    if ($word =~ /$expr/) {
       for my $j (-5 .. 5) {
           $words->{$i + $j}++;
       }
    };
}
seek(DATA, $pos, 0);
$i =0;
for my $word (<DATA>)
{
    $i++;
    chomp $word;
    $word = "<$word>" if ($word =~ /$expr/);
    print "$word " if exists $words->{$i};

}



__DATA__
Regular expressions have always been a weak spot for me, and I've got a
 question that's got me stumped. Here's the problem I'm trying to solve.
 I have somewhat large articles of text (returned from a search), what I'd
 like to do is capture the word and X number of words before and after it
 while tagging the matching word in the captured text. My inital thought
 was to try something like this. The problem I have is that if there is
 more than one term and they overlap, the nth term will not be annotated.
 So my next thought is lookahead/lookbehind, but they don't capture.
 Is there a way to do this with a single regex? Is a regex even the best
 way to do this? Thanks, -Lee