1. 03 Nov, 2004 1 commit
  2. 20 Oct, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-10-20 13:34:04 by simonpj] · f4c9d2b2
      simonpj authored
      ---------------------------------
      	Fix a bug in usage recording
      	---------------------------------
      
      As a result of the new stuff on hi-boot-file consistency checking, I
      accidentally caused Foo.hi to record a usage line for module Foo, and
      this in turn caused rather nasty bad things to happen.  In particular,
      there were occasional crashes of form
      
      ghc-6.3: panic! (the `impossible' happened, GHC version 6.3.20041017):
              forkM Constructor Var.TcTyVar{d r1B9}
      
      At least I think that's why the crash happened.
      
      Anyway, it was certainly a bug, and this commit fixes it.  The main
      payload of this fix is in Desugar.lhs;  the rest is comments and
      tidying.
      f4c9d2b2
  3. 18 Oct, 2004 1 commit
  4. 15 Oct, 2004 1 commit
  5. 01 Oct, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-10-01 13:42:04 by simonpj] · 837824d2
      simonpj authored
      ------------------------------------
      	Simplify the treatment of newtypes
      	Complete hi-boot file consistency checking
      	------------------------------------
      
      In the representation of types, newtypes used to have a special constructor
      all to themselves, very like TyConApp, called NewTcApp.    The trouble is
      that means we have to *know* when a newtype is a newtype, and in an hi-boot
      context we may not -- the data type might be declared as
      	data T
      in the hi-boot file, but as
      	newtype T = ...
      in the source file.  In GHCi, which accumulates stuff from multiple compiles,
      this makes a difference.
      
      So I've nuked NewTcApp.  Newtypes are represented using TyConApps again. This
      turned out to reduce the total amount of code, and simplify the Type data type,
      which is all to the good.
      
      
      This commit also fixes a few things in the hi-boot consistency checking
      stuff.
      837824d2
  6. 30 Sep, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-09-30 10:35:15 by simonpj] · 23f40f0e
      simonpj authored
      ------------------------------------
      	Add Generalised Algebraic Data Types
      	------------------------------------
      
      This rather big commit adds support for GADTs.  For example,
      
          data Term a where
       	  Lit :: Int -> Term Int
      	  App :: Term (a->b) -> Term a -> Term b
      	  If  :: Term Bool -> Term a -> Term a
      	  ..etc..
      
          eval :: Term a -> a
          eval (Lit i) = i
          eval (App a b) = eval a (eval b)
          eval (If p q r) | eval p    = eval q
          		    | otherwise = eval r
      
      
      Lots and lots of of related changes throughout the compiler to make
      this fit nicely.
      
      One important change, only loosely related to GADTs, is that skolem
      constants in the typechecker are genuinely immutable and constant, so
      we often get better error messages from the type checker.  See
      TcType.TcTyVarDetails.
      
      There's a new module types/Unify.lhs, which has purely-functional
      unification and matching for Type. This is used both in the typechecker
      (for type refinement of GADTs) and in Core Lint (also for type refinement).
      23f40f0e
  7. 29 Sep, 2004 1 commit
  8. 15 Sep, 2004 1 commit
    • ross's avatar
      [project @ 2004-09-15 17:48:08 by ross] · daf67985
      ross authored
      arrow notation: allow arrow applications (f -< a) to take a non-empty
      command stack, as suggested by Sebastian Boldt <Sebastian.Boldt@arcor.de>.
      daf67985
  9. 02 Sep, 2004 1 commit
  10. 16 Aug, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-08-16 09:53:47 by simonpj] · 4e325538
      simonpj authored
      -------------------------------
      	Add instance information to :i
       	Get rid of the DeclPool
      	-------------------------------
      
      
      1.  Add instance information to :info command.  GHCi now prints out
          which instances a type or class belongs to, when you use :i
      
      2.  Tidy up printing of unqualified names in user output.
          Previously Outputable.PrintUnqualified was
      	type PrintUnqualified = Name -> Bool
          but it's now
      	type PrintUnqualified = ModuleName -> OccName -> Bool
          This turns out to be tidier even for Names, and it's now also usable
          when printing IfaceSyn stuff in GHCi, eliminating a grevious hack.
      
      3.  On the way to doing this, Simon M had the great idea that we could
          get rid of the DeclPool holding pen, which held declarations read from
          interface files but not yet type-checked.   We do this by eagerly
          populating the TypeEnv with thunks what, when poked, do the type
          checking.   This is just a logical continuation of lazy import
          mechanism we've now had for some while.
      
      The InstPool and RulePool still exist, but I plan to get rid of them in
      the same way.  The new scheme does mean that more rules get sucked in than
      before, because previously the TypeEnv was used to mean "this thing was needed"
      and hence to control which rules were sucked in.  But now the TypeEnv is
      populated more eagerly => more rules get sucked in.  However this problem
      will go away when I get rid of the Inst and Rule pools.
      
      I should have kept these changes separate, but I didn't.  Change (1)
      affects mainly
      	TcRnDriver, HscMain, CompMan, InteractiveUI
      whereas change (3) is more wide ranging.
      4e325538
  11. 13 Aug, 2004 1 commit
  12. 19 Jul, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-07-19 11:29:34 by simonpj] · c92ad297
      simonpj authored
      Template Haskell improvements
      
      a) Make '() and '[] work.
      b) Add tupleTypeName, tupleDataName
      b) Try to improve error message for (lack of) existential data constructors in TH
      c92ad297
  13. 02 Jun, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-06-02 08:23:43 by simonpj] · 5568d10f
      simonpj authored
      -------------------------------
      	Fix a grevious bug in DsMeta
      	which caused a seg fault
      	-------------------------------
      
      The bug was an incorrectly declared type for one of the Template
      Haskell construction functions in DsMeta (repRecCon, repRecUpd)
      and some associated jiggery pokery.
      
      -dcore-lint showed it up nicely, because the desugarer generated
      ill-typed code.
      
      DsMeta PrelNames TH.Lib
      5568d10f
  14. 01 Jun, 2004 1 commit
    • igloo's avatar
      [project @ 2004-06-01 23:22:30 by igloo] · 5ca86c67
      igloo authored
      Add missing functions to TH export list (mostly spotted by Duncan Coutts).
      
      Update TH test output.
      
      Add TH support for patterns with type signatures, and test for same
      (requested by Isaac Jones).
      
      Add TH support for pattern guards, and tests for same
      (requested by Isaac Jones).
      
      Add infix patterns to TH datatypes.
      
      Added Lift instances for 2- to 7-tuples (requested by Duncan Coutts).
      5ca86c67
  15. 25 May, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-05-25 08:09:37 by simonpj] · c6713d35
      simonpj authored
      -----------------------------------------------
      	Improve location info on unused-import warnings
      	-----------------------------------------------
      
      Improving the location involves plumbing the location of the import a bit
      more assiduously -- hence change to imp_mods in TcRnTypes
      c6713d35
  16. 06 Apr, 2004 2 commits
  17. 05 Apr, 2004 2 commits
    • simonpj's avatar
      [project @ 2004-04-05 10:52:23 by simonpj] · 25ef3ade
      simonpj authored
      Remove the entirely-redundant location from the argument of 
      constructor HsPredTy,
          so that we have
      	HsPredTy HsType
          rather than
      	HsPredTy LHsType
      25ef3ade
    • simonpj's avatar
      [project @ 2004-04-05 10:35:11 by simonpj] · 86b3c951
      simonpj authored
      In the derived code for gunfold, use a wild-card for the 
      final case, to avoid a redundant test, and to eliminate the
      annoying warning about un-matched cases.
      
      While I'm at it, rename HsUtils.wildPat to nlWildPat, for
      consistency.
      86b3c951
  18. 02 Apr, 2004 3 commits
    • simonpj's avatar
      [project @ 2004-04-02 16:51:45 by simonpj] · c244ae2a
      simonpj authored
      Wibble to last commit
      c244ae2a
    • simonpj's avatar
      [project @ 2004-04-02 16:46:57 by simonpj] · 40888e1d
      simonpj authored
      Extend the "newtype deriving" feature a little bit more
      (at the request of Wolfgang Jeltsch)
      
      Here's the example:
          class C a b
          instance C [a] Char
          newtype T = T Char deriving( C [a] )
      
      Perfectly sensible, and no reason it should not work.
      Fixing this required me to generalise the abstract syntax of
      a 'deriving' item, hence the non-local effects.
      40888e1d
    • igloo's avatar
      [project @ 2004-04-02 02:39:26 by igloo] · 427ce38d
      igloo authored
      Add support for foreign imports inside quasi-quotes.
      Gave TH a few more uniques to play with and fixed a typo.
      427ce38d
  19. 17 Mar, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-03-17 13:59:06 by simonpj] · af5a2151
      simonpj authored
      ------------------------
      	More newtype clearing up
      	------------------------
      
      * Change the representation of TyCons so that it accurately reflects
      	* data     (0 or more constrs)
      	* newtype  (1 constr)
      	* abstract (unknown)
        Replaces DataConDetails and AlgTyConFlavour with AlgTyConRhs
      
      * Add IfaceSyn.IfaceConDecls, a kind of stripped-down analogue
        of AlgTyConRhs
      
      * Move NewOrData from BasicTypes to HsDecl (it's now an HsSyn thing)
      
      * Arrange that Type.newTypeRep and splitRecNewType_maybe unwrap just
        one layer of new-type-ness, leaving the caller to recurse.
      
        This still leaves typeRep and repType in Type.lhs; these functions
        are still vaguely disturbing and probably should get some attention.
      
      Lots of knock-on changes.  Fixes bug in ds054.
      af5a2151
  20. 24 Feb, 2004 1 commit
    • simonpj's avatar
      [project @ 2004-02-24 15:57:52 by simonpj] · 53fe9413
      simonpj authored
      ---------------------------------------
        	 Record dependency on Template Haskell package
      	  ---------------------------------------
      
      An unforseen consequence of making the Template Haskell package separate
      is that we need to record dependency on the package, even if no TH module
      is imported.  So we carry round (another) mutable variable tcg_th_used in
      the tyepchecker monad, and zap it when $(...) and [| ... |] are used.
      
      I did a little tidy-up and documentation in ListSetOps too
      53fe9413
  21. 23 Jan, 2004 1 commit
    • simonmar's avatar
      [project @ 2004-01-23 13:55:28 by simonmar] · 29da2cf3
      simonmar authored
      Some small steps in the direction of making GHC useable as a library:
      
        - The ErrMsg type is now richer: we keep the location info and the
          PrintUnqualified separate until the message is printed out, and
          messages have a short summary and "extra info", where the extra
          info is used for things like the context info in the typechecker
          (stuff that you don't normally want to see in a more visual setting,
          where the context is obvious because you're looking at the code).
      
        - hscMain now takes an extra argument of type (Messages -> IO ()),
          which says what to do with the error messages.  In normal usage,
          we just pass ErrUtils.printErrorsAndWarnings, but eg. a development
          environment will want to do something different.  The direction we
          need to head in is for hscMain to *never* do any output to
          stdout/stderr except via abstractions like this.
      29da2cf3
  22. 15 Jan, 2004 1 commit
  23. 05 Jan, 2004 2 commits
    • simonpj's avatar
      [project @ 2004-01-05 12:11:42 by simonpj] · 3721dd37
      simonpj authored
      ---------------------------------------
      	  Don't expose constructors as vigorously
      	  ---------------------------------------
      
      GHC used to expose the constructors of a data type in the interface file,
      even if (a) we were not optimising, and (b) the constructors are not exported.
      
      In practice this isn't really necessary, and it's bad because it forces too
      much recompilation.  I've been meaning to fix this for some while.
      
      Now the data cons are hidden, even in the interface file, if both (a) and (b)
      are true.  That means less interface file wobbling.
      
      Mind you, the interface file still changes, because the to/from functions for
      generic type classes change their types.  But provided you don't use them, you'll
      get "compilation not required".
      
      We could play the same game for classes (by hiding their class ops) but that'd
      mean we'd have to change the data type for IfaceClassDecl, and I can't be
      bothered to do that today.  It's unusual to have a class which exports none
      of its methods anyway.
      
      
      
      On the way, I changed the representation of tcg_exports and mg_exports (from
      Avails to NameSet), but that should be externally invisible.
      3721dd37
    • simonpj's avatar
      [project @ 2004-01-05 09:35:39 by simonpj] · 623e5fbb
      simonpj authored
      Buglet in desugaring instance declarations
      623e5fbb
  24. 04 Jan, 2004 1 commit
    • igloo's avatar
      [project @ 2004-01-04 01:48:04 by igloo] · 6da2fdc8
      igloo authored
      Split the pretty-printer out - pprint will now give you pretty much
      anything you are likely to want to pretty-print as a String. For a Doc
      you need (to_HPJ_Doc . ppr), which could be made nicer if it is widely
      used.
      
      Also took the opportunity to do a bit of module renaming and fixed the
      odd typo here and there.
      6da2fdc8
  25. 30 Dec, 2003 1 commit
    • simonpj's avatar
      [project @ 2003-12-30 16:29:17 by simonpj] · f714e6b6
      simonpj authored
      ----------------------------
              Re-do kind inference (again)
      	----------------------------
      
         [WARNING: interface file binary representation has
         (as usual) changed slightly; recompile your libraries!]
      
      Inspired by the lambda-cube, for some time GHC has used
      	type Kind = Type
      That is, kinds were represented by the same data type as types.
      
      But GHC also supports unboxed types and unboxed tuples, and these
      complicate the kind system by requiring a sub-kind relationship.
      Notably, an unboxed tuple is acceptable as the *result* of a
      function but not as an *argument*.  So we have the following setup:
      
      		 ?
      		/ \
      	       /   \
      	      ??   (#)
      	     /  \
                  *   #
      
      where	*    [LiftedTypeKind]   means a lifted type
      	#    [UnliftedTypeKind] means an unlifted type
      	(#)  [UbxTupleKind]     means unboxed tuple
      	??   [ArgTypeKind]      is the lub of *,#
      	?    [OpenTypeKind]	means any type at all
      
      In particular:
      
        error :: forall a:?. String -> a
        (->)  :: ?? -> ? -> *
        (\(x::t) -> ...)	Here t::?? (i.e. not unboxed tuple)
      
      All this has beome rather difficult to accommodate with Kind=Type, so this
      commit splits the two.
      
        * Kind is a distinct type, defined in types/Kind.lhs
      
        * IfaceType.IfaceKind disappears: we just re-use Kind.Kind
      
        * TcUnify.unifyKind is a distinct unifier for kinds
      
        * TyCon no longer needs KindCon and SuperKindCon variants
      
        * TcUnify.zapExpectedType takes an expected Kind now, so that
          in TcPat.tcMonoPatBndr we can express that the bound variable
          must have an argTypeKind (??).
      
      The big change is really that kind inference is much more systematic and
      well behaved.  In particular, a kind variable can unify only with a
      "simple kind", which is built from * and (->).  This deals neatly
      with awkward questions about how we can combine sub-kinding with type
      inference.
      
      Lots of small consequential changes, especially to the kind-checking
      plumbing in TcTyClsDecls.  (We played a bit fast and loose before, and
      now we have to be more honest, in particular about how kind inference
      works for type synonyms.  They can have kinds like (* -> #), so
      
      This cures two long-standing SourceForge bugs
      
      * 753777 (tcfail115.hs), which used erroneously to pass,
        but crashed in the code generator
            type T a = Int -> (# Int, Int #)
            f :: T a -> T a
            f t = \x -> case t x of r -> r
      
      * 753780 (tc167.hs), which used erroneously to fail
            f :: (->) Int# Int#
      
      
      Still, the result is not entirely satisfactory.  In particular
      
      * The error message from tcfail115 is pretty obscure
      
      * SourceForge bug 807249 (Instance match failure on openTypeKind)
        is not fixed.  Alas.
      f714e6b6
  26. 17 Dec, 2003 1 commit
    • simonpj's avatar
      [project @ 2003-12-17 11:29:40 by simonpj] · ca0b7c66
      simonpj authored
      -----------------------------------------------------
        Fix a subtle loop in the context-reduction machinery
        ----------------------------------------------------
      
      This bug was provoked by a recent change: when trying to prove
      a constraint C, TcSimplify.reduce now adds C to the database before
      trying to prove C, thus building recursive dictionaries.
      
      Two bugs
      a) If we add C's superclasses (which we were) we can now build a
         bogusly-recursive dictionary (see Note [SUPERCLASS-LOOP]).
         Solution: in reduce, add C only (via addIrred NoSCs) and then
         later use addWanted to add its definition plus SCs.
      
      b) Since we can have recursive definitions, the superclass-loop
         handling machinery (findAllDeps) must carry its visited-set
         with it (which it was not doing before)
      
      
      The main file is TcSimplify; but I modified a bunch of others to
      take advantage of new function extendVarSetList
      ca0b7c66
  27. 16 Dec, 2003 1 commit
    • simonpj's avatar
      [project @ 2003-12-16 16:24:55 by simonpj] · cb2be98a
      simonpj authored
      --------------------
      	Towards type splices
      	--------------------
      
      Starts the move to supporting type splices, by making
      HsExpr.HsSplice a separate type of its own, and adding
      HsSpliceTy constructor to HsType.
      cb2be98a
  28. 10 Dec, 2003 1 commit
    • simonmar's avatar
      [project @ 2003-12-10 14:15:16 by simonmar] · 55042138
      simonmar authored
      Add accurate source location annotations to HsSyn
      -------------------------------------------------
      
      Every syntactic entity in HsSyn is now annotated with a SrcSpan, which
      details the exact beginning and end points of that entity in the
      original source file.  All honest compilers should do this, and it was
      about time GHC did the right thing.
      
      The most obvious benefit is that we now have much more accurate error
      messages; when running GHC inside emacs for example, the cursor will
      jump to the exact location of an error, not just a line somewhere
      nearby.  We haven't put a huge amount of effort into making sure all
      the error messages are accurate yet, so there could be some tweaking
      still needed, although the majority of messages I've seen have been
      spot-on.
      
      Error messages now contain a column number in addition to the line
      number, eg.
      
         read001.hs:25:10: Variable not in scope: `+#'
      
      To get the full text span info, use the new option -ferror-spans.  eg.
      
         read001.hs:25:10-11: Variable not in scope: `+#'
      
      I'm not sure whether we should do this by default.  Emacs won't
      understand the new error format, for one thing.
      
      In a more elaborate editor setting (eg. Visual Studio), we can arrange
      to actually highlight the subexpression containing an error.  Eventually
      this information will be used so we can find elements in the abstract
      syntax corresponding to text locations, for performing high-level editor
      functions (eg. "tell me the type of this expression I just highlighted").
      
      Performance of the compiler doesn't seem to be adversely affected.
      Parsing is still quicker than in 6.0.1, for example.
      
      Implementation:
      
      This was an excrutiatingly painful change to make: both Simon P.J. and
      myself have been working on it for the last three weeks or so.  The
      basic changes are:
      
       - a new datatype SrcSpan, which represents a beginning and end position
         in a source file.
      
       - To reduce the pain as much as possible, we also defined:
      
            data Located e = L SrcSpan e
      
       - Every datatype in HsSyn has an equivalent Located version.  eg.
      
            type LHsExpr id = Located (HsExpr id)
      
         and pretty much everywhere we used to use HsExpr we now use
         LHsExpr.  Believe me, we thought about this long and hard, and
         all the other options were worse :-)
      
      
      Additional changes/cleanups we made at the same time:
      
        - The abstract syntax for bindings is now less arcane.  MonoBinds
          and HsBinds with their built-in list constructors have gone away,
          replaced by HsBindGroup and HsBind (see HsSyn/HsBinds.lhs).
      
        - The various HsSyn type synonyms have now gone away (eg. RdrNameHsExpr,
          RenamedHsExpr, and TypecheckedHsExpr are now HsExpr RdrName,
          HsExpr Name, and HsExpr Id respectively).
      
        - Utilities over HsSyn are now collected in a new module HsUtils.
          More stuff still needs to be moved in here.
      
        - MachChar now has a real Char instead of an Int.  All GHC versions that
          can compile GHC now support 32-bit Chars, so this was a simplification.
      55042138
  29. 17 Nov, 2003 1 commit
  30. 06 Nov, 2003 1 commit
    • simonpj's avatar
      [project @ 2003-11-06 17:09:50 by simonpj] · 1f5e5580
      simonpj authored
      ------------------------------------
      	Major increment for Template Haskell
      	------------------------------------
      
      1.  New abstract data type "Name" which appears where String used to be.
          E.g. 	data Exp = VarE Name | ...
      
      2.  New syntax 'x and ''T, for quoting Names.  It's rather like [| x |]
          and [t| T |] respectively, except that
      
      	a) it's non-monadic:  'x :: Name
      	b) you get a Name not an Exp or Type
      
      3.  reify is an ordinary function
      	reify :: Name -> Q Info
          New data type Info which tells what TH knows about Name
      
      4.  Local variables work properly.  So this works now (crashed before):
      	f x = $( [| x |] )
      
      5.  THSyntax is split up into three modules:
      
        Language.Haskell.TH		TH "clients" import this
      
        Language.Haskell.TH.THSyntax	data type declarations and internal stuff
      
        Language.Haskell.TH.THLib	Support library code (all re-exported
      				by TH), including smart constructors and
      				pretty printer
      
      6.  Error reporting and recovery are in (not yet well tested)
      
      	report :: Bool {- True <=> fatal -} -> String -> Q ()
      	recover :: Q a -> Q a -> Q a
      
      7.  Can find current module
      
      	currentModule :: Q String
      
      
      Much other cleaning up, needless to say.
      1f5e5580
  31. 04 Nov, 2003 1 commit
  32. 30 Oct, 2003 4 commits
    • simonpj's avatar
      [project @ 2003-10-30 16:01:49 by simonpj] · 57573e7e
      simonpj authored
      This commit does a long-overdue tidy-up
      
      * Remove PprType (gets rid of one more bunch of hi-boot files)
      
      * Put pretty-printing for types in TypeRep
      
      * Make a specialised pretty-printer for Types, rather than
        converting to IfaceTypes and printing those
      57573e7e
    • simonpj's avatar
      [project @ 2003-10-30 10:14:59 by simonpj] · fc6b0049
      simonpj authored
      1.  When desugaring a [d| ... |], do not gensym the method names of
          an instance declaration, else we get very confused!
      
      2.  We don't need to make fresh Names in DsMeta.mkGenSym, because
          the existing Name will do, I believe.  We'll do the genSym when
          we *run* the splice.  (This stuff makes my head hurt.)
      
          Assuming this is so, we can simplify the mkGenSym stuff still more.
      fc6b0049
    • simonpj's avatar
      [project @ 2003-10-30 09:33:30 by simonpj] · 5a0fa261
      simonpj authored
      Updating TH; not finished
      5a0fa261
    • simonpj's avatar
      [project @ 2003-10-30 09:03:15 by simonpj] · 8fc898cb
      simonpj authored
      Remove redundant param from allUses
      8fc898cb