CS计算机代考程序代写 type const = True | False | Int of int

type const = True | False | Int of int
type var = string
type op = Plus | Minus | Times | Div | Lt | Gt | Le | Ge | Eq | And | Or
type value = Const of const
| Fun of var * exp
| Op of op
and exp = Var of var
| Value of value
| Let of var * exp * exp
| If of exp * exp * exp
| App of exp * exp