#15100: `ApplicativeDo` needlessly uses `join` too much -------------------------------------+------------------------------------- Reporter: ekmett | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.4.2 (CodeGen) | Resolution: | Keywords: ApplicativeDo Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by simonpj): * cc: simonmar (added) Comment: cc'ing Simon Marlow, the king of `ApplicativeDo`. Whatever emerges, I'd love to see it expressed in the language of the paper. I found the division in the paper (into a dependency analysis followed by desugaring) to be very helpful. If we could have a typeset appendix that gives the ''actual'' rules followed by GHC (including improvements described above) that would be incredibly helpful. Both for understanding the code, and for helping others who implement `ApplicativeDo` in their compilers. We can easily make the paper source code available. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15100#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler