framework/js/dist-typings/common/extend.d.ts

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/**
* Extend an object's method by running its output through a mutating callback
* every time it is called.
*
* The callback accepts the method's return value and should perform any
* mutations directly on this value. For this reason, this function will not be
* effective on methods which return scalar values (numbers, strings, booleans).
*
* Care should be taken to extend the correct object in most cases, a class'
* prototype will be the desired target of extension, not the class itself.
*
* @example <caption>Example usage of extending one method.</caption>
* extend(Discussion.prototype, 'badges', function(badges) {
* // do something with `badges`
* });
*
* @example <caption>Example usage of extending multiple methods.</caption>
* extend(IndexPage.prototype, ['oncreate', 'onupdate'], function(vnode) {
* // something that needs to be run on creation and update
* });
*
* @param object The object that owns the method
* @param methods The name or names of the method(s) to extend
* @param callback A callback which mutates the method's output
*/
export declare function extend<T extends object, K extends KeyOfType<T, Function>>(object: T, methods: K | K[], callback: (this: T, val: ReturnType<T[K]>, ...args: Parameters<T[K]>) => void): void;
/**
* Override an object's method by replacing it with a new function, so that the
* new function will be run every time the object's method is called.
*
* The replacement function accepts the original method as its first argument,
* which is like a call to `super`. Any arguments passed to the original method
* are also passed to the replacement.
*
* Care should be taken to extend the correct object in most cases, a class'
* prototype will be the desired target of extension, not the class itself.
*
* @example <caption>Example usage of overriding one method.</caption>
* override(Discussion.prototype, 'badges', function(original) {
* const badges = original();
* // do something with badges
* return badges;
* });
*
* @example <caption>Example usage of overriding multiple methods.</caption>
* extend(Discussion.prototype, ['oncreate', 'onupdate'], function(original, vnode) {
* // something that needs to be run on creation and update
* });
*
* @param object The object that owns the method
* @param methods The name or names of the method(s) to override
* @param newMethod The method to replace it with
*/
export declare function override<T extends object, K extends KeyOfType<T, Function>>(object: T, methods: K | K[], newMethod: (this: T, orig: T[K], ...args: Parameters<T[K]>) => void): void;