function handleMapOfConstructs(map) {
        return start

        /** @type {State} */
        function start(code) {
          const left = code !== null && map[code]
          const all = code !== null && map.null
          const list = [
            // To do: add more extension tests.
            /* c8 ignore next 2 */
            ...(Array.isArray(left) ? left : left ? [left] : []),
            ...(Array.isArray(all) ? all : all ? [all] : [])
          ]

          return handleListOfConstructs(list)(code)
        }
      }
Handle a list of construct.

@param {ConstructRecord} map
  Constructs.
@returns {State}
  State.