comment "--" ;
token FIdent letter (letter | digit | '_')*;

entrypoints Program, Exp ;

-- Top level definitions
Prog. Program ::= [Func] ;
terminator Func ";" ;

Func. Func ::= "def" FIdent "=" Exp;

EVar.     Exp9 ::= FIdent ;
EInt.     Exp9 ::= Integer ;
ETrue.    Exp9 ::= "true" ;
EFalse.   Exp9 ::= "false" ;
EApp.     Exp8 ::= Exp8 Exp9 ;
ENeg.	  Exp7 ::= "-" Exp7 ;
EMul.     Exp6 ::= Exp6 "*" Exp7 ;
EDiv.     Exp6 ::= Exp6 "/" Exp7 ;
EAdd.     Exp5 ::= Exp5 "+" Exp6 ;
ESub.     Exp5 ::= Exp5 "-" Exp6 ;
ELt.      Exp4 ::= Exp4 "<" Exp5 ;
EGt.      Exp4 ::= Exp4 ">" Exp5 ;
ELEq.     Exp4 ::= Exp4 "<=" Exp5 ;
EGEq.     Exp4 ::= Exp4 ">=" Exp5 ;
EEq.      Exp3 ::= Exp3 "==" Exp4 ;
ENEq.     Exp3 ::= Exp3 "!=" Exp4 ;
EIf.      Exp2 ::= "if" Exp3 "then" Exp3 "else" Exp3 ;
ELambda.  Exp ::= "\\" FIdent ":" Type "." Exp ;
coercions Exp 9 ;
separator Exp "," ;

TBool. Type1 ::= "Bool" ;
TInt.  Type1 ::= "Int" ;
TFun.  Type ::= Type1 "->" Type ;
coercions Type 1 ;