export interface INgmDataSource<T = {}> {
    data: T[];
    getChildrenFn: (obj: T) => T[];
}
export declare class NgmDataSource<T> implements INgmDataSource<T> {
    data: T[];
    getChildrenFn: (obj: T) => T[];
    constructor(data?: T[], getChildrenFn?: (obj: T) => T[]);
}
export declare function isNotFalsy<T>(value: T | undefined): value is T;