Javascript Map Object with multiple keys to one value


Is it possible to have multiple keys giving the same result in a JS Map, without having to write all of them ?

For example:

const mp = new Map<number, string>([
      [2 || 4, 'even'],
      [1 || 3, 'odd']

This does not work but I am looking for something similar to avoid a switch case which is very verbose

>Solution :

You can write your own helper to transform a less verbose input into the more verbose one which new Map() expects:

const mapReducer = (arr, [keys, val]) => [
    ? [ => [key, val])]
    : [[keys, val]]

const mp = new Map([
  [[2, 4], 'even'],
  [[1, 3], 'odd'],
  [0, 'meh...']
].reduce(mapReducer, []));


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