Weak hands cannot be planted, meager skills have no foundation. Shallow wisdom is futile, how can one hope for a good name?扰扰从役倦，屑屑身事微。少壮轻年月，迟暮惜光辉。
* @package Text_Diff
*/
class Text_Diff_Engine_xdiff {
/**
*/
function diff($from_lines, $to_lines)
{
array_walk($from_lines, array('Text_Diff', 'trimNewlines'));
array_walk($to_lines, array('Text_Diff', 'trimNewlines'));
/* Convert the two input arrays into strings for xdiff processing. */
$from_string = implode("\n", $from_lines);
$to_string = implode("\n", $to_lines);
/* Diff the two strings and convert the result to an array. */
$diff = xdiff_string_diff($from_string, $to_string, count($to_lines));
$diff = explode("\n", $diff);
/* Walk through the diff one line at a time. We build the $edits
* array of diff operations by reading the first character of the
* xdiff output (which is in the "unified diff" format).
*
* Note that we don't have enough information to detect "changed"
* lines using this approach, so we can't add Text_Diff_Op_changed
* instances to the $edits array. The result is still perfectly
* valid, albeit a little less descriptive and efficient