#9980: TcS monad is too heavy -------------------------------------+------------------------------------- Reporter: simonpj | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.4 Resolution: | Keywords: | TypeCheckerPlugins 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 adamgundry): * cc: darchon, nfrisby (added) Comment: I don't think `unsafeTcPluginTcM` should block this refactoring, provided we can provide `unsafeTcPluginTcS` and make sure that `TcS` is still sufficiently well-equipped. What "sufficiently well-equipped" means is a bit hard to pin down, but it should at least support the existing `TcPluginM` API. I think we should preserve the ability to do lookups in `TcPluginM`. For example, `ghc-typelits-knownnat` needs `mkNaturalExpr`, which relies on lookup (via `MonadThings`). I guess in that case one could copy code and refactor so as to do the lookups once, but in general I can imagine a plugin wanting to look up things that are not known at initialisation time. We should probably just make `TcPluginM` instantiate `MonadThings`. Perhaps Christiaan or Nick can comment on other use cases for `unsafeTcPluginTcM`? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9980#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler