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|
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% %
% Frown --- An LALR(k) parser generator for Haskell 98 %
% Copyright (C) 2001-2005 Ralf Hinze %
% %
% This program is free software; you can redistribute it and/or modify %
% it under the terms of the GNU General Public License (version 2) as %
% published by the Free Software Foundation. %
% %
% This program is distributed in the hope that it will be useful, %
% but WITHOUT ANY WARRANTY; without even the implied warranty of %
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the %
% GNU General Public License for more details. %
% %
% You should have received a copy of the GNU General Public License %
% along with this program; see the file COPYING. If not, write to %
% the Free Software Foundation, Inc., 59 Temple Place - Suite 330, %
% Boston, MA 02111-1307, USA. %
% %
% Contact information %
% Email: Ralf Hinze <ralf@cs.uni-bonn.de> %
% Homepage: http://www.informatik.uni-bonn.de/~ralf/ %
% Paper mail: Dr. Ralf Hinze %
% Institut für Informatik III %
% Universität Bonn %
% Römerstraße 164 %
% 53117 Bonn, Germany %
% %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%-------------------------------= --------------------------------------------
\section{|Generate.lhs|}
%-------------------------------= --------------------------------------------
> module Generate
> where
> import Atom
> import Lexer2
> import Haskell
> import Grammar
> import LR0
> import qualified OrdUniqListSet as Set
> import OrdUniqListSet ( Set )
> import Base
> --import Char ( toLower, toUpper )
> import Data.List ( intersperse )
Symbols.
> argsOf :: Symbol -> [Expr]
>-- argsOf = map fst . quotesOf . pattern
> argsOf = attributes
>
> typesOf :: Symbol -> [Type]
>-- typesOf = map snd . quotesOf . pattern
> typesOf = types
> fresh, anonymous, bottoms :: Symbol -> Pat
> fresh v = combine (pattern v) [ v_i i | i <- [1 ..] ]
> anonymous v = replace anon (pattern v)
> bottoms v = replace hsUndefined (pattern v)
> genVars :: Symbol -> [Expr]
> genVars v = [ v_i i | i <- [1 .. length (typesOf v)] ]
Monadic actions.
> --eval args e = foldr eval e (zip [1 ..] args)
> -- where eval (i, ts) x = ts <>>=> Fun [v_i i] x
> evaluate :: [Pat] -> ([Pat] -> Expr) -> Expr
> evaluate args cont = eval ([ (v_i i, arg) | (i, arg) <- zip [1 ..] args]) []
> where eval [] es = cont es
> eval ((v, ts) : as) es= case monadic ts of
> Nothing -> eval as (es ++ [ts])
> Just ts' -> ts' <>>=> Fun [v] (eval as (es ++ [v]))
> monadic :: Expr -> Maybe Expr
> monadic (TypeOf (Varsym "%" : ts) us)
> = Just (TypeOf ts us)
> monadic (Quoted (Varsym "%" : ts))
> = Just (Quoted ts)
> monadic _ = Nothing
Expected tokens.
> expected :: Set Symbol -> Expr
> expected lookahead = List [ Literal s | t <- Set.toList lookahead, Just s <- [shorthand t] ]
> --expected lookahead = List [ bottoms t | t <- Set.toList lookahead ]
Helper functions.
> unCon, unVar :: Expr -> Ident
> unCon (Con x) = x
> unCon _ = impossible "Generate.unCon"
> unVar (Var x) = x
> unVar _ = impossible "Generate.unVar"
> mangle :: Symbol -> String
> mangle v = show (number v) -- number
> smangle :: State -> String
> smangle s = show (snumber s)
> imangle :: Item -> String
> imangle i = show (inumber i)
> pmangle :: Action -> String
> pmangle p = show (pnumber p)
> vmangle :: Int -> Symbol -> String
> vmangle i v = concat (glue (safeName v : map (vmangle (i + 1)) (safeArguments v)))
> where
> glue = intersperse (replicate i '_')
>
> safeName :: Symbol -> String
> safeName (Terminal { number = n })
> = show n
> safeName (Nonterminal { name = s, types = ts })
> = string s ++ "'" ++ show (length ts)
>
> safeArguments :: Symbol -> [Symbol]
> safeArguments (Terminal {}) = []
> safeArguments (Nonterminal { arguments = vs })
> = vs
> asPat :: Expr -> Pat -> Expr
> asPat (Var x) p = As x p
> asPat _ _ = impossible "Generate.asPat"
> {-
> consOf :: Expr -> Ident
> consOf (Var s) = s
> consOf (App p _p') = consOf p
> consOf _ = impossible "Generate.consOf"
> hasHash :: Expr -> Bool
> hasHash e = head (consOf e) == '#'
> rmHash :: Expr -> Ident
> rmHash e = tail (consOf e)
> -}
Names. NB. |v_i| should only be used if there is \emph{no} danger of
name capture.
> v_i :: Int -> Expr
> v_i i = var ("v" ++ show i)
User supplied functions.
> hsFrown, result_tcon, terminal_tcon
> :: Expr
> hsFrown = var "frown"
> result_tcon = con "Result"
> terminal_tcon = con "Terminal"
|
