javascript variable as object key

                                    var key = "happyCount";
var obj = {};
obj[key] = someValueArray;
myArray.push(obj);

                                    var fighters = new WeakMap();
var bruce = {name: 'Bruce Lee'};
var chuck = {name: 'Chuck Norris'};

fighters.set(bruce, 'Jeet Kune Do');
fighters.set(chuck, 'Karate');

console.log(fighters.get(bruce)); // Jeet Kune Do
console.log(fighters.get(chuck)); // Karate

                                    var key = "happyCount";
var obj = {};
obj[key] = someValueArray;
myArray.push(obj);

                                    //For ES6 and Babel
{
    [yourKeyVariable]: "yourValue",
}

// ES5 Alternative
// Create the object first, then use [] to set your variable as a key
var yourObject = {};

yourObject[yourKeyVariable] = "yourValue";