| > Is Haddock a part of GHC? I don't know. If it's not, then whatever | > parser it's using will have to be extended to support pattern | synonyms. | | Haddock uses GHC's parser, but it will need to be taught about pattern | synonyms and how to render them in documentation. Yes, it's in utils/haddock in the main tree, and that really does need to be done before release. | One of the things that we ought to be able to do with this extension is | to provide abstract datatypes with pattern matching support. The only | thing missing is support for exhaustive pattern matches. F# active | patterns has it! We already lack exhaustiveness support as soon as we have guards or view patterns. But it seems a bit more feasible with pattern synonyms. Something to add to the "missing features" list! Simon