vue-property-decorator/lib/decorators/Watch.js

property decorators for Vue Component

import { createDecorator } from 'vue-class-component';
/**
 * decorator of a watch function
 * @param  path the path or the expression to observe
 * @param  WatchOption
 * @return MethodDecorator
 */
export function Watch(path, options) {
    if (options === void 0) { options = {}; }
    var _a = options.deep, deep = _a === void 0 ? false : _a, _b = options.immediate, immediate = _b === void 0 ? false : _b;
    return createDecorator(function (componentOptions, handler) {
        if (typeof componentOptions.watch !== 'object') {
            componentOptions.watch = Object.create(null);
        }
        var watch = componentOptions.watch;
        if (typeof watch[path] === 'object' && !Array.isArray(watch[path])) {
            watch[path] = [watch[path]];
        }
        else if (typeof watch[path] === 'undefined') {
            watch[path] = [];
        }
        watch[path].push({ handler: handler, deep: deep, immediate: immediate });
    });
}