Program. Program ::= [Bind] ;


Bind. Bind ::= Ident ":" Type ";"
               Ident [Ident] "=" Exp ;

EAnn.   Exp5 ::= "(" Exp ":" Type ")" ;
EId.    Exp4 ::= Ident ;
EInt.   Exp4 ::= Integer ;
EApp.   Exp3 ::= Exp3 Exp4 ;
EAdd.   Exp1 ::= Exp1 "+" Exp2 ;
ELet.   Exp ::= "let" Ident "=" Exp "in" Exp ; 
EAbs.   Exp  ::= "\\" Ident "." Exp ;

TMono. Type1 ::= "Mono" Ident ;
TPol. Type1 ::= "Poly" Ident ;
TArr. Type ::= Type1 "->" Type ;

-- This doesn't seem to work so we'll have to live with ugly keywords for now
-- token Upper (upper (letter | digit | '_')*) ;
-- token Lower (lower (letter | digit | '_')*) ;

separator Bind ";" ;
separator Ident " ";

coercions Type 1 ;
coercions Exp 5 ;

comment "--" ;
comment "{-" "-}" ;