elasticlunr/lib/trimmer.js

Lightweight full-text search engine in Javascript for browser search and offline search.

/*!
 * elasticlunr.trimmer
 * Copyright (C) @YEAR Oliver Nightingale
 * Copyright (C) @YEAR Wei Song
 */

/**
 * elasticlunr.trimmer is a pipeline function for trimming non word
 * characters from the begining and end of tokens before they
 * enter the index.
 *
 * This implementation may not work correctly for non latin
 * characters and should either be removed or adapted for use
 * with languages with non-latin characters.
 *
 * @module
 * @param {String} token The token to pass through the filter
 * @return {String}
 * @see elasticlunr.Pipeline
 */
elasticlunr.trimmer = function (token) {
  if (token === null || token === undefined) {
    throw new Error('token should not be undefined');
  }

  return token
    .replace(/^\W+/, '')
    .replace(/\W+$/, '');
};

elasticlunr.Pipeline.registerFunction(elasticlunr.trimmer, 'trimmer');