src/Common/CodeIgniter/Libraries/FormValidation.php
public function is($sValue, $sExpected)
    {
        if ($sValue !== $sExpected) {
            $this->set_message('is', 'This field must be exactly "' . $sExpected . '"');
            return false;
        }

        return true;
    }
public function is($sValue, $sExpected)
    {
        if ($sValue !== $sExpected) {
            $this->set_message('is', 'This field must be exactly "' . $sExpected . '"');
            return false;
        }

        return true;
    }
public function is ( $ sValue , $ sExpected ) { if ( $ sValue !== $ sExpected ) { $ this -> set_message ( 'is' , 'This field must be exactly "' . $ sExpected . '"' ) ; return false ; } return true ; }
Determines whether a value is specifically something

@param string $sValue    The value to check
@param string $sExpected The expected value

@return bool
Determines whether a value is specifically something