|Version 8 (modified by ross@…, 7 years ago)|
- Type Classes with Functional Dependencies (paper) by Mark P. Jones, in ESOP 2000. A semi-formal description of a more restricted system than implemented by GHC and Hugs.
- Sound and Decidable Type Inference for Functional Dependencies by Gregory J. Duck, Simon Peyton Jones, Peter J. Stuckey and Martin Sulzmann, in ESOP 2004. ( extended version)
- Description from the GHC User's manual.
- Problem with functional dependencies (email) by Simon Peyton Jones - is there a conclusion here? Further work?
- In GHC and Hugs for a long time.
- Recently, some problems with FDs have been identified, see also the material on AssociatedTypes.
- There are (at least) three different versions of FDs:
- Mark Jones' original proposal. Problem: It excludes some uses of FDs.
- GHC's implementation. Problem: It makes type checking undecidable. (See Duck et al. for an example.)
- Chameleon's implementation. Problem: Needs type inference based on constraint handling rules (not just HM). Doesn't support separate compilation atm.