## Exercise 6

Moderator: Konzepte der Programmiersprachen

dlorych
Erstie
Beiträge: 17
Registriert: 25. Apr 2015 13:05

### Exercise 6

Hi,

im a bit confused by the first question in Exercise 6. It references a RCFLAE Interpreter with immediate Substitution and one with cyclic environments. In the Repository are two RCFLAE Interpreters, but as far as i understood they are basically the same, just using two different data structures to represent cyclic environments.
So where is the RCFLAE Interpreter with immediate Substitution? Also, as far as i understood, Recursion is not possible without cyclic environments?

Greetings and thanks!

mirko-koehler
Moderator
Beiträge: 66
Registriert: 16. Okt 2017 12:28

### Re: Exercise 6

I appended a link for the RCFLAE interpreter with cyclic environments [1] and immediate substitution [2].
Also, as far as i understood, Recursion is not possible without cyclic environments?
We saw multiple ways to implement recursion. For example, we implmented recrsion with fix-point combinators (in an interpreter without environments) in Exercise 5.

[1] https://repository.st.informatik.tu-dar ... erp.scala
[2] https://repository.st.informatik.tu-dar ... terp.scala