String::extract PHP Method

    public static function extract($string)
    {
        preg_match_all('%:([a-zA-Z-_]+)%', $string, $extracted);
        return $extracted[1];
    }

 /**
  * @testdox extract should extract :vars from a string
  */
 public function testExtractShouldExtractVarsFromAString()
 {
     $expected = array('extract', 'vars');
     $actual = String::extract(':extract :vars');
     $this->assertEquals($expected, $actual);
 }