Expression is obsolete

[hanjoosten]

In the theory, the word term is used where we are still used to using the word expression. @stefjoosten has changed all occurrences in the documentation, but this still has to be done in the Haskell code. When this is done at the wrong time, this can cause major merge conflicts. Therefore, we have to do this only when there are no large code changes in the pipeline. At current, the Namespaces change is on its way, so we do not want to do this now.

• In Haskell code:
  • [ ] Rename Term to PTerm
  • [ ] Rename Expression to ATerm
  • [ ] find all other instances of data definitions with the word expression and rename if appropriate
• In formalAmpersand:
  • [ ] Rename relations appropriately, and make sure to synchronize with Transformers.hs