protected Binop(Expr expr1, Expr expr2)
{
Expr1 = expr1;
Expr2 = expr2;
}
public Mul(Expr expr1, Expr expr2)
: base(expr1, expr2)
{
}
public Sub(Expr expr1, Expr expr2)
: base(expr1, expr2)
{
}
public Add(Expr expr1, Expr expr2)
: base(expr1, expr2)
{
}