import { Stream } from 'xstream'; export declare type Predicate = (ev: any) => boolean; export declare type PreventDefaultOpt = boolean | Predicate | Comparator; export declare type Comparator = { [key: string]: any; }; export declare function fromEvent(element: Element | Document, eventName: string, useCapture?: boolean, preventDefault?: PreventDefaultOpt, passive?: boolean): Stream; export declare function preventDefaultConditional(event: any, preventDefault: PreventDefaultOpt): void;