docs: function grams(value) {
      var nGrams = []
      var index
  
      if (value === null || value === undefined) {
        return nGrams
      }
  
      value = value.slice ? value : String(value)
      index = value.length - n + 1
  
      if (index < 1) {
        return nGrams
      }
  
      while (index--) {
        nGrams[index] = value.slice(index, index + n)
      }
  
      return nGrams
    }