enumerateChoices.js

const enumerateChoices = (sets) => {
  if (sets.length === 0) {
    return [[]];
  }

  const subChoices = enumerateChoices(sets.slice(1));

  return [].concat(...sets[0].map(
    choice => subChoices.map(choices => [choice].concat(choices))
  ));
};

export default enumerateChoices;

Example usage:

import enumerateChoices from './enumerateChoices.js';

const namedSets = {
  color: ['yellow', 'green', 'red'],
  fruit: ['banana', 'apple', 'rhubarb'],
  instrument: ['piano', 'flute', 'violin']
};

const sets = Object.keys(namedSets).map(name => namedSets[name]);

console.log(
  enumerateChoices(sets)
    .map(choices => choices.join(' '))
    .join('\n')
);

Output:

yellow banana piano
yellow banana flute
yellow banana violin
yellow apple piano
yellow apple flute
yellow apple violin
yellow rhubarb piano
yellow rhubarb flute
yellow rhubarb violin
green banana piano
green banana flute
green banana violin
green apple piano
green apple flute
green apple violin
green rhubarb piano
green rhubarb flute
green rhubarb violin
red banana piano
red banana flute
red banana violin
red apple piano
red apple flute
red apple violin
red rhubarb piano
red rhubarb flute
red rhubarb violin