Es6 1 a uno
const map = new Map([
[ 1, 'one' ],
[ 2, 'two' ],
[ 3, 'three' ], // trailing comma is ignored
]);
Poised Piranha
const map = new Map([
[ 1, 'one' ],
[ 2, 'two' ],
[ 3, 'three' ], // trailing comma is ignored
]);