js str.length code example

Example 1: js countKeys

let count = Object.keys(myobj).length

Example 2: string length javascript

/* The length property of a String object contains the length of the
string, in UTF-16 code units. length is a read-only data property of
string instances. */

const str = "Life, the universe and everything. Answer:";
console.log(`${str} ${str.length}`);
// expected output: "Life, the universe and everything. Answer: 42"

Example 3: js promiseStatus

/**
 * This function allow you to modify a JS Promise by adding some status properties.
 * Based on: http://stackoverflow.com/questions/21485545/is-there-a-way-to-tell-if-an-es6-promise-is-fulfilled-rejected-resolved
 * But modified according to the specs of promises : https://promisesaplus.com/
 */
function MakeQuerablePromise(promise) {
    // Don't modify any promise that has been already modified.
    if (promise.isResolved) return promise;

    // Set initial state
    var isPending = true;
    var isRejected = false;
    var isFulfilled = false;

    // Observe the promise, saving the fulfillment in a closure scope.
    var result = promise.then(
        function(v) {
            isFulfilled = true;
            isPending = false;
            return v; 
        }, 
        function(e) {
            isRejected = true;
            isPending = false;
            throw e; 
        }
    );

    result.isFulfilled = function() { return isFulfilled; };
    result.isPending = function() { return isPending; };
    result.isRejected = function() { return isRejected; };
    return result;
}

Example 4: js

JavaScript (JS) is a lightweight, interpreted, or just-in-time compiled
programming language with first-class functions.

While it is most well-known as the scripting language for Web pages,
many non-browser environments also use it, such as Node.js, Apache
CouchDB and Adobe Acrobat.