Start ::= Exp;

abstract Exp;
MulExp: Exp ::= LeftExp:Exp RightExp:Exp;
DivExp: Exp ::= LeftExp:Exp RightExp:Exp;
LetExp: Exp ::= Binding* Exp;
Binding ::= IdExp Exp;
FPLitExp: Exp ::= <FPLIT>;
IdExp: Exp ::= <ID>;
AskUserExp: Exp ::= [Exp];