src/Config/Argument.php
public function defaultValue($value) {
        $this->validated = false;
        $this->config[self::DEFAULT_VALUE] = $value;
        return $this;
    }
public function defaultValue($value) {
        $this->validated = false;
        $this->config[self::DEFAULT_VALUE] = $value;
        return $this;
    }
public function defaultValue ( $ value ) { $ this -> validated = false ; $ this -> config [ self :: DEFAULT_VALUE ] = $ value ; return $ this ; }
set the argument's default value

@param mixed $value
@return $this
set the argument s default value