NAME
    Text::Context::EitherSide - Get n words either side of search keywords

SYNOPSIS
      use Text::Context::EitherSide;

      my $text = "The quick brown fox jumped over the lazy dog";
      my $context = Text::Context::EitherSide->new($text);

      $context->as_string("fox") # "... quick brown fox jumped over ..."

      $context->as_string("fox", "jumped") 
        # "... quick brown fox jumped over the ..."
  
      my $context = Text::Context::EitherSide->new($text, context => 1);
        # 1 word on either side
  
      $context->as_string("fox", "jumped", "dog");
        # "... brown fox jumped over ... lazy dog",

    Or, if you don't believe in all this OO rubbish:

      use Text::Context::EitherSide qw(get_context);
      get_context(1, $text, "fox", "jumped", "dog") 
            # "... brown fox jumped over ... lazy dog"

DESCRIPTION
    Suppose you have a large piece of text - typically, say, a web page or a
    mail message. And now suppose you've done some kind of full-text search
    on that text for a bunch of keywords, and you want to display the
    context in which you found the keywords inside the body of the text.

    A simple-minded way to do that would be just to get the two words either
    side of each keyword. But hey, don't be too simple minded, because
    you've got to make sure that the list doesn't overlap. If you have

        the quick brown fox jumped over the lazy dog

    and you extract two words either side of "fox", "jumped" and "dog", you
    really don't want to end up with

        quick brown fox jumped over brown fox jumped over the the lazy dog

    so you need a small amount of smarts. This module has a small amount of
    smarts.

EXPORTABLE
  get_context
    This is primarily an object-oriented module. If you don't care about
    that, just import the "get_context" subroutine, and call it like so:

        get_context($num_of_words, $text, @words_to_find)

    and you'll get back a string with ellipses as in the synopsis. That's
    all that most people need to know. But if you want to do clever stuff...

METHODS
  new
        my $c = Text::Context::EitherSite->new($text [, context=> $n]);

    Create a new object storing some text to be searched, plus optionally
    some information about how many words on either side you want. (If you
    don't like the default of 2.)

  context
        $c->context(5);

    Allows you to get and set the number of the words on either side.

  as_sparse_list
        $c->as_sparse_list(@keywords)

    Returns the keywords, plus *n* words on either side, as a sparse list;
    the original text is split into an array of words, and non-contextual
    elements are replaced with "undef"s. (That's not actually how it works,
    but conceptually, it's the same.)

  as_list
        $c->as_list(@keywords)

    The same as "as_sparse_list", but single or multiple "undef"s are
    collapsed into a single ellipsis:

        (undef, "foo", undef, undef, undef, "bar")

    becomes

        ("...", "foo", "...", "bar")

  as_string
        $c->as_string(@keywords)

    Takes the "as_list" output above and joins them all together into a
    string. This is what most people want from "Text::Context::EitherSide".

  EXPORT
    "get_context" is available as a shortcut for

       Text::Context::EitherSide->new($text, context => $n)->as_string(@words);

    but needs to be explicitly imported. Nothing is exported by default.

SEE ALSO
    Text::Context is an even smarter way of extracting a contextual string.

AUTHOR
    Current maintainer: Tony Bowden

    Original author: Simon Cozens

BUGS and QUERIES
    Please direct all correspondence regarding this module to:
    bug-Text-Context-EitherSide@rt.cpan.org

COPYRIGHT AND LICENSE
    Copyright 2002-2005 by Kasei Limited, http://www.kasei.com/

    You may use and redistribute this module under the terms of the Artistic
    License.

