var compress = phrase => {
    var mots = [];                                 // Tableau des mots uniques
    for (m of phrase.toLowerCase().split(' '))     // On parcourt chaque mot
         if (!mots.includes(m)) mots.push(m)       // Nouveau mot ? On l'ajoute
    return mots     
}

compress('The number 0 is such a strange number Strangely it has zero meaning')

var compress = phrase => {
  decoup = phrase.toLowerCase().split(' ')
  mots = decoup.reduce((a, m) => a.includes(m) ? a : a.concat(m), [])
  return mots
}

compress('The number 0 is such a strange number Strangely it has zero meaning')

[1, 5, 10].map(v => v * v)     // On met chaque élément au carré

['abra','cada','bra'].map(m => m[0].toUpperCase()) // 1ere lettre en majuscule

var compress = phrase => {
  decoup = phrase.toLowerCase().split(' ')
  mots = decoup.reduce((a, m) => a.includes(m) ? a : a.concat(m), [])
  return decoup.map(m => '' + mots.indexOf(m)).join('') 
}

compress('The number 0 is such a strange number Strangely it has zero meaning')

var compress = phrase => {
  decoup = phrase.toLowerCase().split(' ')
  mots = [...new Set(decoup)]     // Liste des mots uniques
  return decoup.map(m => '' + mots.indexOf(m)).join('') 
}

compress('The number 0 is such a strange number Strangely it has zero meaning')