1. 21 Jun, 2007 1 commit
    • David Himmelstrup's avatar
      Add several new record features · 2eb04ca0
      David Himmelstrup authored
      1. Record disambiguation (-fdisambiguate-record-fields)
      
      In record construction and pattern matching (although not
      in record updates) it is clear which field name is intended
      even if there are several in scope.  This extension uses
      the constructor to disambiguate.  Thus
      	C { x=3 }
      uses the 'x' field from constructor C (assuming there is one)
      even if there are many x's in scope.
      
      
      2. Record punning (-frecord-puns)
      
      In a record construction or pattern match or update you can 
      omit the "=" part, thus
      	C { x, y }
      This is just syntactic sugar for
      	C { x=x, y=y }
      
      
      3.  Dot-dot notation for records (-frecord-dot-dot)
      
      In record construction or pattern match (but not update) 
      you can use ".." to mean "all the remaining fields".  So
      
      	C { x=v, .. }
      
      means to fill in the remaining fields to give
      
      	C { x=v, y=y }
      
      (assuming C has fields x and y).  This might reasonably
      considered very dodgy stuff.  For pattern-matching it brings
      into scope a bunch of things that are not explictly mentioned;
      and in record construction it just picks whatver 'y' is in
      scope for the 'y' field.   Still, Lennart Augustsson really
      wants it, and it's a feature that is extremely easy to explain.
      
      
      Implementation
      ~~~~~~~~~~~~~~
      I thought of using the "parent" field in the GlobalRdrEnv, but
      that's really used for import/export and just isn't right for this.
      For example, for import/export a field is a subordinate of the *type
      constructor* whereas here we need to know what fields belong to a
      particular *data* constructor.
      
      The main thing is that we need to map a data constructor to its
      fields, and we need to do so in the renamer.   For imported modules
      it's easy: just look in the imported TypeEnv.  For the module being
      compiled, we make a new field tcg_field_env in the TcGblEnv.
      The important functions are
      	RnEnv.lookupRecordBndr
      	RnEnv.lookupConstructorFields
      
      There is still a significant infelicity in the way the renamer
      works on patterns, which I'll tackle next.
      
      
      I also did quite a bit of refactoring in the representation of
      record fields (mainly in HsPat).***END OF DESCRIPTION***
      
      Place the long patch description above the ***END OF DESCRIPTION*** marker.
      The first line of this file will be the patch name.
      
      
      This patch contains the following changes:
      
      M ./compiler/deSugar/Check.lhs -3 +5
      M ./compiler/deSugar/Coverage.lhs -6 +7
      M ./compiler/deSugar/DsExpr.lhs -6 +13
      M ./compiler/deSugar/DsMeta.hs -8 +8
      M ./compiler/deSugar/DsUtils.lhs -1 +1
      M ./compiler/deSugar/MatchCon.lhs -2 +2
      M ./compiler/hsSyn/Convert.lhs -3 +3
      M ./compiler/hsSyn/HsDecls.lhs -9 +25
      M ./compiler/hsSyn/HsExpr.lhs -13 +3
      M ./compiler/hsSyn/HsPat.lhs -25 +63
      M ./compiler/hsSyn/HsUtils.lhs -3 +3
      M ./compiler/main/DynFlags.hs +6
      M ./compiler/parser/Parser.y.pp -13 +17
      M ./compiler/parser/RdrHsSyn.lhs -16 +18
      M ./compiler/rename/RnBinds.lhs -2 +2
      M ./compiler/rename/RnEnv.lhs -22 +82
      M ./compiler/rename/RnExpr.lhs -34 +12
      M ./compiler/rename/RnHsSyn.lhs -3 +2
      M ./compiler/rename/RnSource.lhs -50 +78
      M ./compiler/rename/RnTypes.lhs -50 +84
      M ./compiler/typecheck/TcExpr.lhs -18 +18
      M ./compiler/typecheck/TcHsSyn.lhs -20 +21
      M ./compiler/typecheck/TcPat.lhs -8 +6
      M ./compiler/typecheck/TcRnMonad.lhs -6 +15
      M ./compiler/typecheck/TcRnTypes.lhs -2 +11
      M ./compiler/typecheck/TcTyClsDecls.lhs -3 +4
      M ./docs/users_guide/flags.xml +7
      M ./docs/users_guide/glasgow_exts.xml +42
      2eb04ca0
  2. 18 Jun, 2007 1 commit
  3. 07 Jun, 2007 3 commits
    • David Himmelstrup's avatar
      Fix a bug in MatchCon, and clarify what dataConInstOrigArgTys does · 00b6d256
      David Himmelstrup authored
      There was an outright bug in MatchCon.matchOneCon, in the construction
      of arg_tys.  Easily fixed.  It never showed up becuase the arg_tys are
      only used in WildPats, and they in turn seldom have their types looked
      (except by hsPatType).  So I can't make a test case for htis.
      
      While I was investigating, I added a bit of clarifation and
      invariant-checking to dataConInstOrigArgTys and dataConInstArgTys
      00b6d256
    • David Himmelstrup's avatar
      Do not perform a worker/wrapper split for a NOINLINE function · 481b014b
      David Himmelstrup authored
      This came up in an email exchange with Duncan Coutts in May 2007.
      If a function is marked NOINLINE there is really no point in 
      doing a worker/wrapper split, because the wrapper will never
      be inlined.
      
      481b014b
    • David Himmelstrup's avatar
      Fix Trac #1402: typo in specialiser · 7dd96d1d
      David Himmelstrup authored
      This patch fixes a plain bug in the specialiser (rhs_bndrs instead
      of rhs_ids) which made GHC crash in obscure cases.  
      
      It exposed a case in which we might not do all possible specialisation;
      see Note [Specialisation shape].  It's not an important case, but I've
      added a warning in DEBUG mode.
      
      Trac #1402.  Test is spec003.hs
      7dd96d1d
  4. 21 Jun, 2007 2 commits
  5. 20 Jun, 2007 14 commits
  6. 19 Jun, 2007 8 commits
  7. 18 Jun, 2007 2 commits
  8. 17 Jun, 2007 1 commit
  9. 13 Jun, 2007 1 commit
  10. 17 Jun, 2007 1 commit
  11. 16 Jun, 2007 1 commit
  12. 15 Jun, 2007 2 commits
  13. 14 Jun, 2007 1 commit
  14. 13 Jun, 2007 2 commits