LazyRecord\Schema\DeclareSchema::addColumn PHP 메소드

    public function addColumn(DeclareColumn $column)
    {
        if (isset($this->columns[$column->name])) {
            throw new Exception("column {$name} of " . get_class($this) . ' is already defined.');
        }
        $this->columnNames[] = $column->name;
        return $this->columns[$column->name] = $column;
    }