code: function cachePush(value) {
      var cache = this.cache,
          type = typeof value;
  
      if (type == 'boolean' || value == null) {
        cache[value] = true;
      } else {
        if (type != 'number' && type != 'string') {
          type = 'object';
        }
        var key = type == 'number' ? value : keyPrefix + value,
            typeCache = cache[type] || (cache[type] = {});
  
        if (type == 'object') {
          (typeCache[key] || (typeCache[key] = [])).push(value);
        } else {
          typeCache[key] = true;
        }
      }
    }
docs: Adds a given value to the corresponding cache object.
  
  @private
  @param {*} value The value to add to the cache.