reduce return array of objects es code example
Example 1: reduce object to array javascript
var arr = [{x:1},{x:2},{x:4}];
arr.reduce(function (a, b) {
return {x: a.x + b.x}; // returns object with property x
})
// ES6
arr.reduce((a, b) => ({x: a.x + b.x}));
// -> {x: 7}
Example 2: .reduce mdn
arr.reduce(callback( accumulator, currentValue[, index[, array]] )[, initialValue])