> remove FixityResolution from the context-free grammar
http://hackage.haskell.org/trac/haskell-prime/wiki/FixityResolution
Please take a look and comment. This fixes a nasty bug in the Haskell syntax - albeit one that doesn't cause problems in practice, but still. I think the changes make the grammar look nicer, and help compiler implementers by providing a sample implementation of fixity resolution.
We better be sure the sample implementation is correct! I've tested it fairly well, but I wouldn't rule out corner cases being wrong, especially with prefix negation.
The code in Resolve.hs has been used by HLint for months, and is the basis of the resolution used in haskell-src-exts 1.0.0. In that time I haven't seen any bugs with the fixity resolution.
I updated the code on the wiki page: the previous version didn't handle prefix negation - did you implement that yourself in HLint?
No, I didn't implement prefix negation in HLint - it never came up as an issue. Perhaps the underlying HSE library dealt with it for me - Niklas would know. Thanks Neil