import { Selector } from "./Selector";
import { KeyDesc } from "./KeyDesc";
import { OpDesc } from "./OpDesc";
export declare class LtDesc extends OpDesc {
    readonly type: string;
    constructor(key: string | KeyDesc, value: Selector);
    lookup(source: any): (target: any) => boolean;
}
export declare function Lt(key: string | KeyDesc, value: Selector): LtDesc;