Learn to navigate Javascript objects efficiently using Object.keys(), Object.values(), and Object.entries() methods to access and manipulate data.
The JavaScriptfor/ofstatement loops through the values of an iterable objects. for/oflets you loop over data structures that are iterable such as Arrays, Strings, Maps, NodeLists, and more. Thefor/ofloop has the following syntax: for(variableofiterable) { ...
The keys before, after, beforeEach, and afterEach are special-cased, object values are suites, and function values are test-cases: module.exports = { before: function() { // ... }, Array: { '#indexOf()': { 'should return -1 when not present': function() { [1, 2, 3].index...
You can minify more than one JavaScript file at a time by using an object for the first argument where the keys are file names and the values are source code: var code = { "file1.js": "function add(first, second) { return first + second; }", "file2.js": "console.log(add(1 ...
Jessie has no for/in statement, and so does not inherit the non-determinism regarding property modification during for/in enumeration. Everything useful about for/in is still available byObject.keys,Object.valuesandObject.entries, (or in TinySES through reflection) but without this non-determinism...
Possible Values:"average" |"color-burn" |"color-dodge" |"color" |"darken" |"destination-atop" |"destination-in" |"destination-out" |"destination-over" |"difference" |"exclusion" |"hard-light" |"hue" |"invert" |"lighten" |"lighter" |"luminosity" |"minus" |"multiply" |"normal" |...
Methods are properties whose values are functions. Kinds of Properties There are three kinds of properties: Properties (or named data properties) Normal properties in an object—that is, mappings from string keys to values. Named data properties include methods. This is by far the most common ...
If your field is a string or number and your array of values are also either strings or numbers you can utilise $fastIn which is an optimised $in query that uses indexOf() to identify matching values instead of looping over all items in the array of values and running a new matching ...
to iterate over arrays, and Object.keys() / Object.values() / Object.entries() to produce arrays so you can iterate over objects. const numbers = [1, 2, 3, 4, 5]; // bad let sum = 0; for (let num of numbers) { sum += num; } sum === 15; // good let sum = 0; ...
to iterate over arrays, and Object.keys() / Object.values() / Object.entries() to produce arrays so you can iterate over objects. const numbers = [1, 2, 3, 4, 5]; // bad let sum = 0; for (let num of numbers) { sum += num; } sum === 15; // good let sum = 0; ...