How to generate a list of all combinations with Javascript Generators

generate.js

const letters = 'abcdefghijklmnopqrstuvxyzæøå'
const numbers = '0123456789'

const list = (letters + numbers).split('')

exports.generate = function* generate(length) {
  function* gen(length) {
    for(var i = 0; i < list.length; i++) {
      if(length > 1) {
        for (const val of gen(length - 1)) {
          yield list[i] + val
        }
      } else {
        yield list[i]
      }
    }
  }
  for(var i = 1; i <= length; i++) {
    for (const val of gen(i)) {
      yield val
    }
  }
}