1. 11 Jul, 2012 1 commit
  2. 10 Jul, 2012 1 commit
    • Simon Peyton Jones's avatar
      More changes to kind inference for type and class declarations · 3fe3ef50
      Simon Peyton Jones authored
      These should fix #7024 and #7022, among others.
      
      The main difficulty was that we were getting occ-name clashes
      between kind and type variables in TyCons, when spat into an
      interface file. The new scheme is to tidy TyCons during the
      conversoin into IfaceSyn, rather than trying to generate them
      pre-tidied, which was the already-unsatisfactory previous plan.
      
      There is the usual wave of refactorig as well.
      3fe3ef50
  3. 25 Jun, 2012 2 commits
  4. 22 Jun, 2012 1 commit
  5. 08 Jun, 2012 1 commit
    • dimitris's avatar
      Significant refactoring of TcSimplify, in particular simplifyInfer and · 3891a056
      dimitris authored
      simplifyTop, code beautification etc. Important things:
      
      (a) New top-level defaulting plan, gotten rid of the SimplContext field.
          See Note [Top-level Defaulting Plan]
      
      (b) Serious bug fix in the floatEqualities mechanism
          See Note [Extra TcS Untouchables],[Float Equalities out of Implications]
      
      The changes are mostly confined in TcSimplify but there is a
      simplification wave affecting other modules as well.
      3891a056
  6. 07 Jun, 2012 1 commit
    • Simon Peyton Jones's avatar
      Support polymorphic kind recursion · c9117200
      Simon Peyton Jones authored
      This is (I hope) the last major patch for kind polymorphism.
      The big new feature is polymorphic kind recursion when you
      supply a complete kind signature for a type constructor.
      (I've documented it in the user manual too.)
      
      This fixes Trac #6137, #6093, #6049.
      
      The patch also makes type/data families less polymorphic by default.
         data family T a
      now defaults to T :: * -> *
      If you want T :: forall k. k -> *, use
         data family T (a :: k)
      
      This defaulting to * is done whenever there is a
      "complete, user-specified kind signature", something that is
      carefully defined in the user manual.
      
      Hurrah!
      c9117200
  7. 15 May, 2012 1 commit
  8. 11 May, 2012 1 commit
    • Simon Peyton Jones's avatar
      Refactor LHsTyVarBndrs to fix Trac #6081 · fc8959ac
      Simon Peyton Jones authored
      This is really a small change, but it touches a lot of files quite
      significantly. The real goal is to put the implicitly-bound kind
      variables of a data/class decl in the right place, namely on the
      LHsTyVarBndrs type, which now looks like
      
        data LHsTyVarBndrs name
          = HsQTvs { hsq_kvs :: [Name]
                   , hsq_tvs :: [LHsTyVarBndr name]
            }
      
      This little change made the type checker neater in a number of
      ways, but it was fiddly to push through the changes.
      fc8959ac
  9. 27 Apr, 2012 1 commit
  10. 25 Apr, 2012 1 commit
  11. 24 Apr, 2012 1 commit
  12. 13 Apr, 2012 2 commits
    • Simon Peyton Jones's avatar
      Revert "Added ':runmonad' command to GHCi" · e0e99f99
      Simon Peyton Jones authored
      Two problems, for now at any rate
        a) Breaks the build with lots of errors like
              No instance for (Show (IO ())) arising from a use of `print'
        b) Discussion of the approache hasn't converged yet
           (Simon M had a number of suggestions)
      
      This reverts commit eecd7c98.
      e0e99f99
    • dterei's avatar
      Added ':runmonad' command to GHCi · eecd7c98
      dterei authored
      This command allows you to lift user stmts in GHCi into an IO monad
      that implements the GHC.GHCi.GHCiSandboxIO type class. This allows for
      easy sandboxing of GHCi using :runmonad and Safe Haskell.
      
      Longer term it would be nice to allow a more general model for the Monad
      than GHCiSandboxIO but delaying this for the moment.
      eecd7c98
  13. 04 Apr, 2012 1 commit
  14. 09 Mar, 2012 1 commit
    • parcs's avatar
      Don't defer type errors when evaluating a GHCi expression · 301a718b
      parcs authored
      It is unhelpful here because the expression will get evaluated right
      away anyway, thus emitting a redundant warning followed by an equivalent
      runtime exception. If the expression were an ill-typed pure expression,
      _three_ equivalent type errors would get emitted (due to the two-phase
      typechecking done in 'Plan C')
      301a718b
  15. 02 Mar, 2012 1 commit
    • Simon Peyton Jones's avatar
      Hurrah! This major commit adds support for scoped kind variables, · 3bf54e78
      Simon Peyton Jones authored
      which (finally) fills out the functionality of polymorphic kinds.
      It also fixes numerous bugs.
      
      Main changes are:
      
      Renaming stuff
      ~~~~~~~~~~~~~~
      * New type in HsTypes:
           data HsBndrSig sig = HsBSig sig [Name]
        which is used for type signatures in patterns, and kind signatures
        in types.  So when you say
             f (x :: [a]) = x ++ x
        or
             data T (f :: k -> *) (x :: *) = MkT (f x)
        the signatures in both cases are a HsBndrSig.
      
      * The [Name] in HsBndrSig records the variables bound by the
        pattern, that is 'a' in the first example, 'k' in the second,
        and nothing in the third.  The renamer initialises the field.
      
      * As a result I was able to get rid of
           RnHsSyn.extractHsTyNames :: LHsType Name -> NameSet
        and its friends altogether.  Deleted the entire module!
        This led to some knock-on refactoring; in particular the
        type renamer now returns the free variables just like the
        term renamer.
      
      Kind-checking types: mainly TcHsType
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      A major change is that instead of kind-checking types in two
      passes, we now do one. Under the old scheme, the first pass did
      kind-checking and (hackily) annotated the HsType with the
      inferred kinds; and the second pass desugared the HsType to a
      Type.  But now that we have kind variables inside types, the
      first pass (TcHsType.tc_hs_type) can go straight to Type, and
      zonking will squeeze out any kind unification variables later.
      
      This is much nicer, but it was much more fiddly than I had expected.
      
      The nastiest corner is this: it's very important that tc_hs_type
      uses lazy constructors to build the returned type. See
      Note [Zonking inside the knot] in TcHsType.
      
      Type-checking type and class declarations: mainly TcTyClsDecls
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      I did tons of refactoring in TcTyClsDecls.  Simpler and nicer now.
      
      Typechecking bindings: mainly TcBinds
      ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      I rejigged (yet again) the handling of type signatures in TcBinds.
      It's a bit simpler now.  The main change is that tcTySigs goes
      right through to a TcSigInfo in one step; previously it was split
      into two, part here and part later.
      
      Unsafe coercions
      ~~~~~~~~~~~~~~~~
      Usually equality coercions have exactly the same kind on both
      sides.  But we do allow an *unsafe* coercion between Int# and Bool,
      say, used in
          case error Bool "flah" of { True -> 3#; False -> 0# }
      -->
          (error Bool "flah") |> unsafeCoerce Bool Int#
      
      So what is the instantiation of (~#) here?
         unsafeCoerce Bool Int# :: (~#) ??? Bool Int#
      I'm using OpenKind here for now, but it's un-satisfying that
      the lhs and rhs of the ~ don't have precisely the same kind.
      
      More minor
      ~~~~~~~~~~
      * HsDecl.TySynonym has its free variables attached, which makes
        the cycle computation in TcTyDecls.mkSynEdges easier.
      
      * Fixed a nasty reversed-comparison bug in FamInstEnv:
        @@ -490,7 +490,7 @@ lookup_fam_inst_env' match_fun one_sided ie fam tys
           n_tys = length tys
           extra_tys = drop arity tys
           (match_tys, add_extra_tys)
      -       | arity > n_tys = (take arity tys, \res_tys -> res_tys ++ extra_tys)
      +       | arity < n_tys = (take arity tys, \res_tys -> res_tys ++ extra_tys)
              | otherwise     = (tys,            \res_tys -> res_tys)
      3bf54e78
  16. 10 Feb, 2012 1 commit
    • Simon Peyton Jones's avatar
      Complete fix of #5820 · 15ec8835
      Simon Peyton Jones authored
      There are two related changes in here
      
      a) Fix TcRnDriver.setInteractiveContext so that it initialises
         tcg_insts and tcg_fam_insts, as well as the corresponding
         tcg_inst_env and tcg_fam_inst_env fields.  Vital!
      
      b) Fix FamInst.tcExtendLocalFamInstEnv for the GHCi case.
         It had a special HACK to allow family instances to be overridden
         in GHCi.  Fair enough, but
           * It was only affecting the tcg_fam_inst_env, not tcg_fam_insts
           * It overrode home-package instances as well as ones entered
             at the GHCi prompt, which probably wasn't intended.
      
         I fixed both of these, and also narrowed the scope of what it does
         to override only *identical* instances, rather than any ones that
         conflict.  If people yelp about this we can return to the question,
         but for now it narrows the range of the HACK
      15ec8835
  17. 06 Feb, 2012 1 commit
  18. 26 Jan, 2012 5 commits
  19. 19 Jan, 2012 1 commit
  20. 12 Jan, 2012 1 commit
    • Simon Peyton Jones's avatar
      Implememt -fdefer-type-errors (Trac #5624) · 5508ada4
      Simon Peyton Jones authored
      This patch implements the idea of deferring (most) type errors to
      runtime, instead emitting only a warning at compile time.  The
      basic idea is very simple:
      
       * The on-the-fly unifier in TcUnify never fails; instead if it
         gets stuck it emits a constraint.
      
       * The constraint solver tries to solve the constraints (and is
         entirely unchanged, hooray).
      
       * The remaining, unsolved constraints (if any) are passed to
         TcErrors.reportUnsolved.  With -fdefer-type-errors, instead of
         emitting an error message, TcErrors emits a warning, AND emits
         a binding for the constraint witness, binding it
         to (error "the error message"), via the new form of evidence
         TcEvidence.EvDelayedError.  So, when the program is run,
         when (and only when) that witness is needed, the program will
         crash with the exact same error message that would have been
         given at compile time.
      
      Simple really.  But, needless to say, the exercise forced me
      into some major refactoring.
      
       * TcErrors is almost entirely rewritten
      
       * EvVarX and WantedEvVar have gone away entirely
      
       * ErrUtils is changed a bit:
           * New Severity field in ErrMsg
           * Renamed the type Message to MsgDoc (this change
             touches a lot of files trivially)
      
       * One minor change is that in the constraint solver we try
         NOT to combine insoluble constraints, like Int~Bool, else
         all such type errors get combined together and result in
         only one error message!
      
       * I moved some definitions from TcSMonad to TcRnTypes,
         where they seem to belong more
      5508ada4
  21. 03 Jan, 2012 1 commit
    • Simon Peyton Jones's avatar
      Major refactoring of CoAxioms · 98a642cf
      Simon Peyton Jones authored
      This patch should have no user-visible effect.  It implements a
      significant internal refactoring of the way that FC axioms are
      handled.  The ultimate goal is to put us in a position to implement
      "pattern-matching axioms".  But the changes here are only does
      refactoring; there is no change in functionality.
      
      Specifically:
      
       * We now treat data/type family instance declarations very,
         very similarly to types class instance declarations:
      
         - Renamed InstEnv.Instance as InstEnv.ClsInst, for symmetry with
           FamInstEnv.FamInst.  This change does affect the GHC API, but
           for the better I think.
      
         - Previously, each family type/data instance declaration gave rise
           to a *TyCon*; typechecking a type/data instance decl produced
           that TyCon.  Now, each type/data instance gives rise to
           a *FamInst*, by direct analogy with each class instance
           declaration giving rise to a ClsInst.
      
         - Just as each ClsInst contains its evidence, a DFunId, so each FamInst
           contains its evidence, a CoAxiom.  See Note [FamInsts and CoAxioms]
           in FamInstEnv.  The CoAxiom is a System-FC thing, and can relate any
           two types, whereas the FamInst relates directly to the Haskell source
           language construct, and always has a function (F tys) on the LHS.
      
         - Just as a DFunId has its own declaration in an interface file, so now
           do CoAxioms (see IfaceSyn.IfaceAxiom).
      
         These changes give rise to almost all the refactoring.
      
       * We used to have a hack whereby a type family instance produced a dummy
         type synonym, thus
            type instance F Int = Bool -> Bool
         translated to
            axiom FInt :: F Int ~ R:FInt
            type R:FInt = Bool -> Bool
         This was always a hack, and now it's gone.  Instead the type instance
         declaration produces a FamInst, whose axiom has kind
            axiom FInt :: F Int ~ Bool -> Bool
         just as you'd expect.
      
       * Newtypes are done just as before; they generate a CoAxiom. These
         CoAxioms are "implicit" (do not generate an IfaceAxiom declaration),
         unlike the ones coming from family instance declarations.  See
         Note [Implicit axioms] in TyCon
      
      On the whole the code gets significantly nicer.  There were consequential
      tidy-ups in the vectoriser, but I think I got them right.
      98a642cf
  22. 05 Dec, 2011 1 commit
    • Simon Peyton Jones's avatar
      Allow full constraint solving under a for-all (Trac #5595) · 2e6dcdf7
      Simon Peyton Jones authored
      The main idea is that when we unify
          forall a. t1  ~  forall a. t2
      we get constraints from unifying t1~t2 that mention a.
      We are producing a coercion witnessing the equivalence of
      the for-alls, and inside *that* coercion we need bindings
      for the solved constraints arising from t1~t2.
      
      We didn't have way to do this before.  The big change is
      that here's a new type TcEvidence.TcCoercion, which is
      much like Coercion.Coercion except that there's a slot
      for TcEvBinds in it.
      
      This has a wave of follow-on changes. Not deep but broad.
      
      * New module TcEvidence, which now contains the HsWrapper
        TcEvBinds, EvTerm etc types that used to be in HsBinds
      
      * The typechecker works exclusively in terms of TcCoercion.
      
      * The desugarer converts TcCoercion to Coercion
      
      * The main payload is in TcUnify.unifySigmaTy. This is the
        function that had a gross hack before, but is now beautiful.
      
      * LCoercion is gone!  Hooray.
      
      Many many fiddly changes in conssequence.  But it's nice.
      2e6dcdf7
  23. 29 Nov, 2011 1 commit
    • Simon Peyton Jones's avatar
      Refactor (again) the treatment of record-selector bindings · ac11b1f1
      Simon Peyton Jones authored
      We were generating them from the tcg_tcs field of the TcGblEnv,
      but that goes badly wrong when there are top-level Template
      Haskell splices, because the tcg_tcs field grows successively.
      If we generate record-selector binds for all the TyCons in the
      accumulated list, we generate them multiple times for TyCons
      earlier in the program.  This what was happening in Trac #5665:
        data T = T { x :: Int }
        $(f 4)  -- Top level splice
        ..more code..
      Here the record selector bindings for T were being generated
      twice.
      
      Better instead to generate the record-selector bindings in
      TcTyClsDecls, right where the new TyCons are being declared (as indeed
      they were some time ago).  This pushed me into doing some refactoring:
      instead of returning the record bindings, tcTyAndClassDecls adds them
      to the tcg_binds field of the TcGblEnv.  I think the result is a bit
      nicer, and it has the additional merit of working.
      ac11b1f1
  24. 28 Nov, 2011 1 commit
    • dimitris's avatar
      This patch includes: · f3183d9a
      dimitris authored
      0) Typo in panic message.
      1) prioritization of equalities over family equalities in the worklists.
      2) rewriting of inert substitutions and solveds on-the-spot instead of
         kicking them out in the inerts. This required a monadic map over
         substitutions hence the modifications in UniqFM.
      3) Just comments and removing stale commented code.
      
      4) Useful SCC for simplifyInfer.
      
      5) Making CoreStats outputable.
      f3183d9a
  25. 18 Nov, 2011 1 commit
    • Simon Marlow's avatar
      Track #included files for recompilation checking (#4900, #3589) · 3f34e091
      Simon Marlow authored
      This was pretty straightforward: collect the filenames in the lexer,
      and add them in to the tcg_dependent_files list that the typechecker
      collects.
      
      Note that we still don't get #included files in the ghc -M output.
      Since we don't normally lex the whole file in ghc -M, this same
      mechanism can't be used directly.
      3f34e091
  26. 16 Nov, 2011 3 commits
  27. 11 Nov, 2011 1 commit
    • dreixel's avatar
      New kind-polymorphic core · 09015be8
      dreixel authored
      This big patch implements a kind-polymorphic core for GHC. The current
      implementation focuses on making sure that all kind-monomorphic programs still
      work in the new core; it is not yet guaranteed that kind-polymorphic programs
      (using the new -XPolyKinds flag) will work.
      
      For more information, see http://haskell.org/haskellwiki/GHC/Kinds
      09015be8
  28. 05 Nov, 2011 1 commit
    • GregWeber's avatar
      addDependentFile #4900 · b994313a
      GregWeber authored
      Let GHC know about an external dependency that Template Haskell uses
      so that GHC can recompile when the dependency changes.
      No support for ghc -M
      
      There is a corresponding addition to the template-haskell library
      b994313a
  29. 04 Nov, 2011 1 commit
  30. 01 Nov, 2011 1 commit
  31. 26 Oct, 2011 1 commit
  32. 25 Oct, 2011 1 commit