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  • Committer: Bazaar Package Importer
  • Author(s): Marco Túlio Gontijo e Silva
  • Date: 2009-04-08 20:01:10 UTC
  • mfrom: (1.1.5 upstream)
  • Revision ID: james.westby@ubuntu.com-20090408200110-96hu9fr918e1wsr1
Tags: 0.9.10-0.1
http://bugs.debian.org/523214
* Non-maintainer upload.
* New upstream version.  Closes: #523214.
* Use new version of haskell-devscripts.
* debian/control:
  - Use new Standards-Version.
  - cpphs is not Indep.
* debian/patches: Remove directory.
* debian/haskell-uulib-doc.doc-base: haddock's file are stored now in
  /usr/share/libghc6-uulib-doc/html/.
* debian/haskell-uulib-doc.examples: Create file.

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examples/parser/Scanner.x
 
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{
 
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-- alex scanner for use with uulib
 
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--   compile with alex -o Scanner.hs -g Scanner.x
 
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module Scanner(tokenize) where
 
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import UU.Scanner
 
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}
 
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$litChar   = [^[\" \\]]
 
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$identChar = [a-zA-Z0-9\'_]
 
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tokens :-
 
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  $white+                                      ;                               -- whitespace
 
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  "--".*                                       ;                               -- comment
 
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  \" ($litChar | \\ \\ | \\ \" )* \"           { valueToken TkString }         -- string
 
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  [0-9]+                                       { valueToken TkInteger16 }      -- int
 
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  ( let | in )                                 { reserved }                    -- reserved keywords
 
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  [\(\)\=]                                     { reserved }                    -- reserved symbols
 
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  [\+\*]                                       { reserved }                    -- operators
 
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  [a-zA-Z] $identChar*                         { valueToken TkVarid }          -- identifier
 
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{
 
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-- boilerplate code needed for Alex
 
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type AlexInput = (Pos, String)
 
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alexInputPrevChar :: AlexInput -> Char
 
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alexInputPrevChar = error "alexInputPrevChar: there is no need to go back in the input."
 
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alexGetChar :: AlexInput -> Maybe (Char, AlexInput)
 
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alexGetChar (_, []) = Nothing
 
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alexGetChar (p, (c:cs))
 
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  = let p' = adv p c
 
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    in Just (c, (p', cs))
 
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-- use the Alex scanner to generate a list of tokens for the uulib token parsers
 
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tokenize :: String -> String -> [Token]
 
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tokenize filename str
 
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  = go (initpos, str)
 
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  where
 
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    initpos = Pos 1 1 filename
 
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    go inp@(pos, cs)
 
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      = case alexScan inp 0 of
 
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          AlexEOF         -> []
 
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          AlexError inp'  -> valueToken TkError [head cs] pos : go inp'
 
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          AlexSkip inp' _ -> go inp'
 
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          AlexToken inp' len act -> act (take len cs) pos : go inp'
 
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}
 
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