Question

I am writing a Perl script that is searching for a term in large portions of text. What I would like to display back to the user is a small subset of the text around the search term, so the user can have context of where this search term is used. Google search results are a good example of what I am trying to accomplish, where the context of your search term is displayed under the title of the link.

My basic search is using this:

if ($text =~ /$search/i ) {     print '${title}:${text}\n'; } 

($title contains the title of the item the search term was found in) This is too much though, since sometimes $text will be holding hundreds of lines of text.

This is going to be displayed on the web, so I could just provide the title as a link to the actual text, but there is no context for the user.

I tried modifying my regex to capture 4 words before and 4 words after the search term, but ran into problems if the search term was at the very beginning or very end of $text.

What would be a good way to accomplish this? I tried searching CPAN because I’m sure someone has a module for this, but I can’t think of the right terms to search for. I would like to do this without modules if possible, because getting modules installed here is a pain. Does anyone have any ideas?

Answer 1

Your initial attempt at 4 words before/after wasn’t too far off.

Try:

if ($text =~ /((\S+\s+){0,4})($search)((\s+\S+){0,4})/i) {     my ($pre, $match, $post) = ($1, $3, $4);     ... }