#15711: Kind inference of class variables does not examine associated types -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.1 Resolution: | Keywords: TypeInType Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by Richard Eisenberg ): In [changeset:"5e45ad10ffca1ad175b10f6ef3327e1ed8ba25f3/ghc" 5e45ad10/ghc]: {{{ #!CommitTicketReference repository="ghc" revision="5e45ad10ffca1ad175b10f6ef3327e1ed8ba25f3" Finish fix for #14880. The real change that fixes the ticket is described in Note [Naughty quantification candidates] in TcMType. Fixing this required reworking candidateQTyVarsOfType, the function that extracts free variables as candidates for quantification. One consequence is that we now must be more careful when quantifying: any skolems around must be quantified manually, and quantifyTyVars will now only quantify over metavariables. This makes good sense, as skolems are generally user-written and are listed in the AST. As a bonus, we now have more control over the ordering of such skolems. Along the way, this commit fixes #15711 and refines the fix to #14552 (by accepted a program that was previously rejected, as we can now accept that program by zapping variables to Any). This commit also does a fair amount of rejiggering kind inference of datatypes. Notably, we now can skip the generalization step in kcTyClGroup for types with CUSKs, because we get the kind right the first time. This commit also thus fixes #15743 and #15592, which both concern datatype kind generalisation. (#15591 is also very relevant.) For this aspect of the commit, see Note [Required, Specified, and Inferred in types] in TcTyClsDecls. Test cases: dependent/should_fail/T14880{,-2}, dependent/should_fail/T15743[cd] dependent/should_compile/T15743{,e} ghci/scripts/T15743b polykinds/T15592 dependent/should_fail/T15591[bc] ghci/scripts/T15591 }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15711#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler

#15711: Kind inference of class variables does not examine associated types -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 8.6.1 Resolution: fixed | Keywords: TypeInType Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: indexed- | types/should_compile/T15711 Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Changes (by goldfire): * testcase: => indexed-types/should_compile/T15711 * status: new => closed * resolution: => fixed Comment: Test case added in c1db1eb028b6962bac904975a6730edc6935ca8f -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15711#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler