protected function compileReplace(array $rule)
    {
        return array(
            'regexp' => '([' .
                preg_quote($this->compileCharacter($rule['data']['srcStart'])) . '-' .
                preg_quote($this->compileCharacter($rule['data']['srcEnd'])) .
                '])us',
            'callback' => $this->compileTargetCharacter($rule['data']['dest']),
        );
    }