The articles sounds like an advertisment to use Elm. Immutability and value semantic is enforcd by the language and the typesystem is rich enough to allow to us

The articles sounds like an advertisment to use Elm. Immutability and value semantic is enforcd by the language and the typesystem is rich enough to allow to use generic data sructures while been statically typed. As a functional language Elm has closures allowing to violate separation of data and code and get non-literal data types, but this is strongly discouraged by documentation, runtime (aka Elm architecture) and tools.