ClassNameFormatter

type ClassNameList = Array<string | undefined>
type NoStrictEntityMods = Record<string, string | boolean | number | undefined>
type ClassNameFormatter = (
  elementNameOrBlockModifiers?: NoStrictEntityMods | string | null,
  elementModifiersOrBlockMixins?: NoStrictEntityMods | ClassNameList | null,
  elementMixins?: ClassNameList,
) => string