1. 16 Aug, 2006 1 commit
    • simonpj@microsoft.com's avatar
      Disable form-checking for rule LHSs · 1c36a2c0
      simonpj@microsoft.com authored
      Previously we checked the form of the arguments of a RULE lhs, to 
      ensure that they were simple applications. There was no good reason
      for that, save to prevent you writing LHSs that were unlikely to match.
      And Don Stewart found he wanted to do something we didn't allow (a section,
      I think).  So I have just disabled the check.
  2. 15 Aug, 2006 7 commits
    • simonpj@microsoft.com's avatar
      Allow class and instance decls in hs-boot files · dfcf8852
      simonpj@microsoft.com authored
      For some reason, in 6.5 the manual said you could put a class decl in
      an interface file, but not an instance decl; whereas the implementation
      was exactly the othe way round.
      This patch makes it possible to put *both* class and instance decls
      in an interface file. 
      I also did a bit of re-factoring; comparing the declarations in the
      hs-boot and hs file is now done by converting to IfaceSyn, because we
      have good comparison operations for IfaceSyn already implemented.
      This fixed a bug that previously let through an inconsistent declaration 
      of a data type.
      The remaining infelicity concerns "abstract" TyCons.  They are a bit
      of a hack anyway; and Classes are not handled in the same way.  Need
      to think about this, but I think it's probably ok as it stands.
    • simonpj@microsoft.com's avatar
      Reject derivable type classes with higher-rank methods · 4bcaad0c
      simonpj@microsoft.com authored
      Trac #864 suggested a derivable type class with a higher-rank method.
      In principle this is quite do-able, but in practice the mechanism works
      by generating source code and then doing type inference.  To make this work
      with higher-rank types would require impredicative polymorphism. And we 
      do have that, so it could probably be made to work by generating (source-level)
      type annotations.  But it's real work, so I'm settling for generating a
      decent error message rather than crashing.
    • simonpj@microsoft.com's avatar
      SpecConstr now specialises on constants and lambdas · c17dc70a
      simonpj@microsoft.com authored
      Roman inspired me to beef up SpecConstr to deal with
      a) constant arguments
      b) lambda arguments
      This is described in elaborate comments in the file:
       	Note [Specialising for constant parameters]
      	Note [Specialising for lambda parameters]
      I also took the opportunity to fix the usage analysis done by
      SpecConstr, which was only handling the top-level correctly.
      Now it does nesting too.
    • simonpj@microsoft.com's avatar
      Fix two bugs in rule-matching · 969baa16
      simonpj@microsoft.com authored
      These two typo-like bugs have been there for a long time!
        One concerns the selection of overlapping rules, 
        which was back to front
        The other was name-lining-up bug in the Case case of matching
      This patch also arranges to export matchN. 
        (Not a good name, but still!)
    • simonpj@microsoft.com's avatar
    • simonpj@microsoft.com's avatar
      Make UniqSM into a proper monad · 0d7c6cea
      simonpj@microsoft.com authored
    • simonpj@microsoft.com's avatar
  3. 14 Aug, 2006 5 commits
    • simonpj@microsoft.com's avatar
      Be more conservative about duplicating continuations · da107045
      simonpj@microsoft.com authored
      Roman found that GHC was duplicating continuations that arose (essentially)
      from uses of 'seq', or strict constructors.  This fixes the problem;
      see the comments mkDupableCont (the Select case with a single alternative).
      I'm a little concerned that this may also miss useful case-of-case
      tranformations, so I'd like to know if anyone finds that this patch
      makes performance worse.
      To make it a bit more gung-ho, one could check for all the binders
      being dead, before choosing this new, conservative alternative.
    • simonpj@microsoft.com's avatar
      Inline into tail-called constructor args · 098d99aa
      simonpj@microsoft.com authored
      	x = case y of { True -> (p,q); ... }
      The occurrence analyser was marking p,q as 'Many', because they args
      of a constructor in an RhsCtxt.  But actually they aren't in a RhsCtxt,
      and in this case it's better to inline.
    • simonpj@microsoft.com's avatar
      Improve exprIsCheap · 25ce05f7
      simonpj@microsoft.com authored
      exprIsCheap is meant to return True iff it's ok to push the expression
      inside a lambda.  But the previous version would return True of a nested
      construtor application like (1:2:3:[]), which isn't right.
      This patch re-factors the code somewhat, and fixes the bug.
    • bringert@cs.chalmers.se's avatar
    • simonpj@microsoft.com's avatar
      Improve error message in TcHsType · ef10d0a7
      simonpj@microsoft.com authored
      Fixes Trac #863.
      Test is tcfail162
  4. 11 Aug, 2006 14 commits
  5. 10 Aug, 2006 13 commits