code: function uid (prefix = '', length = 12) {
    const id = `u${_uid('', length - 1)}`
    if (prefix && process.env.NODE_ENV !== 'production') {
      return `${prefix}__${id}`
    } else {
      return id
    }
  }
docs: ---
  category: utilities
  id: uid_doc
  ---
  Generate a unique (CSS-safe) id string
  
  @module uid
  @param {String} prefix a string to prefix the id for debugging in non-production env
  @param {Number} length id length (in characters, minus the prefix)
  @returns {String} a unique id