function search_simplify

Simplifies a string according to indexing rules.

Parameters

$text: Text to simplify.

Return value

Simplified text.

See also

hook_search_preprocess()

File

modules/search/search.module, line 411

Code

function search_simplify($text) {
    // Decode entities to UTF-8
    $text = decode_entities($text);
    // Lowercase
    $text = drupal_strtolower($text);
    // Call an external processor for word handling.
    search_invoke_preprocess($text);
    // Simple CJK handling
    if (variable_get('overlap_cjk', TRUE)) {
        $text = preg_replace_callback('/[' . PREG_CLASS_CJK . ']+/u', 'search_expand_cjk', $text);
    }
    // To improve searching for numerical data such as dates, IP addresses
    // or version numbers, we consider a group of numerical characters
    // separated only by punctuation characters to be one piece.
    // This also means that searching for e.g. '20/03/1984' also returns
    // results with '20-03-1984' in them.
    // Readable regexp: ([number]+)[punctuation]+(?=[number])
    $text = preg_replace('/([' . PREG_CLASS_NUMBERS . ']+)[' . PREG_CLASS_PUNCTUATION . ']+(?=[' . PREG_CLASS_NUMBERS . '])/u', '\\1', $text);
    // Multiple dot and dash groups are word boundaries and replaced with space.
    // No need to use the unicode modifer here because 0-127 ASCII characters
    // can't match higher UTF-8 characters as the leftmost bit of those are 1.
    $text = preg_replace('/[.-]{2,}/', ' ', $text);
    // The dot, underscore and dash are simply removed. This allows meaningful
    // search behavior with acronyms and URLs. See unicode note directly above.
    $text = preg_replace('/[._-]+/', '', $text);
    // With the exception of the rules above, we consider all punctuation,
    // marks, spacers, etc, to be a word boundary.
    $text = preg_replace('/[' . PREG_CLASS_UNICODE_WORD_BOUNDARY . ']+/u', ' ', $text);
    // Truncate everything to 50 characters.
    $words = explode(' ', $text);
    array_walk($words, '_search_index_truncate');
    $text = implode(' ', $words);
    return $text;
}