private function getChangeExtent($fromLine, $toLine)
	{
		$start = 0;
		$limit = min(strlen($fromLine), strlen($toLine));
		while($start < $limit && $fromLine{$start} == $toLine{$start}) {
			++$start;
		}
		$end = -1;
		$limit = $limit - $start;
		while(-$end <= $limit && substr($fromLine, $end, 1) == substr($toLine, $end, 1)) {
			--$end;
		}
		return array(
			$start,
			$end + 1
		);
	}
private function getChangeExtent($fromLine, $toLine)
	{
		$start = 0;
		$limit = min(strlen($fromLine), strlen($toLine));
		while($start < $limit && $fromLine{$start} == $toLine{$start}) {
			++$start;
		}
		$end = -1;
		$limit = $limit - $start;
		while(-$end <= $limit && substr($fromLine, $end, 1) == substr($toLine, $end, 1)) {
			--$end;
		}
		return array(
			$start,
			$end + 1
		);
	}
private function getChangeExtent ( $ fromLine , $ toLine ) { $ start = 0 ; $ limit = min ( strlen ( $ fromLine ) , strlen ( $ toLine ) ) ; while ( $ start < $ limit && $ fromLine { $ start } == $ toLine { $ start } ) { ++ $ start ; } $ end = - 1 ; $ limit = $ limit - $ start ; while ( - $ end <= $ limit && substr ( $ fromLine , $ end , 1 ) == substr ( $ toLine , $ end , 1 ) ) { -- $ end ; } return array ( $ start , $ end + 1 ) ; }
Given two strings, determine where the changes in the two strings
begin, and where the changes in the two strings end.

@param string $fromLine The first string.
@param string $toLine The second string.
@return array Array containing the starting position (0 by default) and the ending position (-1 by default)
Given two strings determine where the changes in the two strings begin and where the changes in the two strings end .