/**
 * binding.ts offers a convenient subscribe() function that creates a binding to an observable, a
 * a plain value, or a function from which it builds a computed.
 */
import { IDisposable } from './dispose';
import { IKnockoutReadObservable, InferKoType } from './kowrap';
import { BaseObservable } from './observable';
import { UseCBOwner } from './subscribe';
/**
 * Any of the value types that DOM methods know how to subscribe to: a plain value (like a
 * string); an Observable (including a Computed); a knockout observable; a function.
 *
 * If a function, it's used to create a `Computed`, and will be called with a context function
 * `use`, allowing it to depend on other observable values (see documentation for `Computed`).
 */
export type BindableValue<T> = BaseObservable<T> | ComputedCallback<T> | T | IKnockoutReadObservable<T>;
export type ComputedCallback<T> = (use: UseCBOwner, ...args: any[]) => T;
/**
 * Subscribes a callback to valueObs, which may be one a plain value, an observable, a knockout
 * observable, or a function. If a function, it's used to create a computed() and will be called
 * with a context function `use`, allowing it to depend on other observable values (see
 * documentation for `computed`).
 *
 * In all cases, `callback(newValue, oldValue)` is called immediately and whenever the value
 * changes. On the initial call, oldValue is undefined.
 *
 * Returns an object which should be disposed to remove the created subscriptions, or null.
 */
export declare function subscribeBindable<KObs extends IKnockoutReadObservable<any>>(valueObs: KObs, callback: (val: InferKoType<KObs>) => void): IDisposable | null;
export declare function subscribeBindable<T>(valueObs: BindableValue<T>, callback: (val: T) => void): IDisposable | null;
/**
 * Subscribes a callback to `valueObs` (which may be a value, observable, or function) using
 * `subscribeBindable()`, and ties the disposal of this subscription to the passed-in element.
 */
export declare function subscribeElem<T>(elem: Node, valueObs: BindableValue<T>, callback: (newVal: T, oldVal?: T) => void): void;