[Haskell-cafe] GHC 7.10 GHC-API Changes and proposed changes.

There are a number of changes in GHC 7.10 that will make it easier for tool writers to use the GHC API. These include 1. More parser entrypoints, to explicitly parse fragments [Andrew Gibiansky] The following parsers are now provided parseModule, parseImport, parseStatement, ​ parseDeclaration, parseExpression, parseTypeSignature, ​ parseFullStmt, parseStmt, parseIdentifier, ​ parseType, parseHeader 2. No more landmines in the AST [Alan Zimmerman] In the past it was difficult to work with the GHC AST as any generic traversals had to carefully tiptoe around an assortment of panic and undefined expressions. These have now been removed, allowing standard traversal libraries to be used. There is a third change currently being discussed, and I would like feedback on it's desirability. 3. Introduce an annotation structure to the ParsedSource to record the location of uncaptured keywords. At the moment the location of let / in / if / then / else / do etc is not captured in the AST. This makes it difficult to parse some source, transform the AST, and then output it again preserving the original layout. The current proposal, which can be seen at [1] and a proof of concept implementation at [2] returns a structure keyed to each AST element containing simply the specific SrcSpan's not already captured in the AST. This is the analogue of the Language.Haskell.Exts.Annotated.Syntax from haskell-src-exts, except a custom SrcSpanInfo structure is provided for each AST element constructor, and it is not embedded within the AST. [1] https://ghc.haskell.org/trac/ghc/wiki/GhcAstAnnotations [2] https://phabricator.haskell.org/D297 So, apart from HaRe, are there any other users who would be interested in using this? Regards Alan -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://www.haskell.org/pipermail/haskell-cafe/attachments/20141001/c2587307/attachment.html>