cvs commit: fptools/happy/alex/examples haskell.x fptools/happy/a lex/src ParseMonad.hs AbsSyn.hs Main.hs Makefile NFA.hs Parser.y Scan.hs Scan.x fptools/happy/alex/templates wrappers.hs GenericTemplate.hs Makefile fptools/happy/alex/tests Makefile simple.x

simonmar    2003/03/31 08:52:26 PST

  Modified files:        (Branch: simonm-hackery-branch)
    happy/alex/examples  haskell.x 
    happy/alex/src       AbsSyn.hs Main.hs Makefile NFA.hs 
                         Parser.y Scan.hs Scan.x 
    happy/alex/templates GenericTemplate.hs Makefile 
    happy/alex/tests     Makefile simple.x 
  Added files:           (Branch: simonm-hackery-branch)
    happy/alex/src       ParseMonad.hs 
    happy/alex/templates wrappers.hs 
  Log:
  Some changes to the programmer's interface to a generated scanner.
  
  Now you get a bare-bones scanner where Alex supplies
  
  	type StartCode
  	alexScan :: AlexInput		 -- The current input
  		 -> StartCode		 -- The "start code"
  		 -> Maybe (           	 -- Nothing on error or EOF
  			     AlexInput,  -- The remaining input
  			     Int,        -- Length of this token
  			     action      -- The action (unknown type)
  			  )
  
  You can use this scanner by supplying the following:
  
  	type AlexInput
  	alexGetChar  :: AlexInput -> Maybe (Char,AlexInput)
  	alexPrevChar :: AlexInput -> Char
  
  or there is a selection of "wrappers" which provide suitable
  definitions for the above.  eg. saying
  
    %wrapper "monad"
  
  in the grammer file gets you a default monad which keeps track of the
  input and can handle parse errors, and
  
    %wrapper "gscan"
  
  gets you an interface similar to the old Alex.
  
  Or alternatively you can build your own monad on top of the bare-bones
  scanner, which is what Alex itself now does.  As a result it can now
  report lexical errors in the grammar file properly.
  
  Revision  Changes    Path
  1.1.2.3   +68 -65    fptools/happy/alex/examples/Attic/haskell.x
  1.1.2.6   +29 -6     fptools/happy/alex/src/Attic/AbsSyn.hs
  1.1.1.1.2.8 +67 -27    fptools/happy/alex/src/Main.hs
  1.2.2.7   +8 -3      fptools/happy/alex/src/Makefile
  1.1.1.1.2.6 +1 -1      fptools/happy/alex/src/NFA.hs
  1.1.2.9   +15 -49    fptools/happy/alex/src/Attic/Parser.y
  1.1.1.1.2.9 +140 -196  fptools/happy/alex/src/Scan.hs
  1.1.1.1.2.7 +96 -73    fptools/happy/alex/src/Scan.x
  1.1.2.6   +41 -154   fptools/happy/alex/templates/Attic/GenericTemplate.hs
  1.1.2.3   +10 -11    fptools/happy/alex/templates/Attic/Makefile
  1.1.2.4   +0 -2      fptools/happy/alex/tests/Attic/Makefile
  1.1.2.4   +25 -18    fptools/happy/alex/tests/Attic/simple.x