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|
{-
An ambiguous grammar (3 reduce/reduce conflicts).
frown --backtrack Fun.g
-}
module Fun
where
import Monad
type Result = []
%{
Terminal = Special ';' | Special ',' | Special '=' | Special '|' | Var;
Nonterminal = bindings | binding | alts | expr | vars | fun;
bindings : bindings, binding;
| ;
binding : fun, vars, Special '=', expr, Special ';', alts;
alts : vars, Special '|', expr, Special ';', alts;
| ;
expr : Var;
| fun, vars;
vars : vars, Var;
| ;
fun : Var;
}%
data Terminal = Special Char | Var
frown _ = fail "syntax error"
|
