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merge

TS JS Deno

Creates a new object from the combination of two or more objects.

Use Array.prototype.reduce() combined with Object.keys(obj) to iterate over all objects and keys. Use hasOwnProperty() and Array.prototype.concat() to append values for keys existing in multiple objects.

typescript
const merge = (...objs: AnyObject[]) =>
[...objs].reduce(
(acc, obj) =>
Object.keys(obj).reduce((a, k) => {
acc[k] = acc.hasOwnProperty(k)
? [].concat(acc[k]).concat(obj[k])
: obj[k];
return acc;
}, {}),
{}
);
typescript
const object = {
a: [{ x: 2 }, { y: 4 }],
b: 1,
};
const other = {
a: { z: 3 },
b: [2, 3],
c: "foo",
};
merge(object, other); // { a: [ { x: 2 }, { y: 4 }, { z: 3 } ], b: [ 1, 2, 3 ], c: 'foo' }