#9768: Declarations processed in unexpected order in the presence of TH declaration splices -------------------------------------+------------------------------------- Reporter: qnikst | Owner: goldfire Type: bug | Status: closed Priority: normal | Milestone: Component: Template | Version: 7.8.3 Haskell | Keywords: Resolution: wontfix | Architecture: Unknown/Multiple Operating System: | Difficulty: Unknown Unknown/Multiple | Blocked By: Type of failure: | Related Tickets: None/Unknown | Test Case: | https://gist.github.com/qnikst/b93e7154e78bcc159be2| Blocking: | Differential Revisions: | -------------------------------------+------------------------------------- Changes (by goldfire): * status: new => closed * resolution: => wontfix Comment: GHC's current behavior is actually exactly as advertised (although perhaps unintuitive). From section 7.16.1 of the manual: A declaration group is the group of declarations created by a top- level declaration splice, plus those following it, down to but not including the next top-level declaration splice. The first declaration group in a module includes all top-level definitions down to but not including the first top-level declaration splice. Thus, in the OP's code, `def "B"` and `main` are in the same group, and accordingly, a splice within that group can't reify the group's own types. This could be changed easily enough, but I think a change would make TH strictly less expressive. Using the current behavior, a splice could include part of a declaration (say, just a type signature) and the rest of the declaration can be hand-written outside the splice. If we made a top- level splice its own inviolable group, such a split declaration would be impossible to write. So, I'm closing this ticket, as everything seems OK to me. Do reopen if this is really ruining your day. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9768#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler