declare namespace Ext {
    export namespace grid {
        export namespace selection {
            export interface ColumnsConfig {
            }

            export class Columns extends Ext.grid.selection.Selection  {
                public isColumns?: boolean;
                public contains(column?: Ext.grid.column.Column): boolean;
                public getColumns(): Ext.grid.column.Column[];
                public getCount(): number;
            }
        }
    }
}