Question

  (* I have a section with many variables and definitions. *)
  Section SectionWithDefs.

    Context {A B C: Type}.

    Variable arg1: A -> B.
    Variable arg2: B -> C.

    (* Functions that uses these variables. *)
    Definition f a := arg2 (arg1 a).  
      ...

  End SectionWithDefs.

  (* Now I want to use some of these functions. *)
  Section AnotherSection.

    Context {A B C: Type}.

    (* Here are the arguments. *)
    Variable arg1: A -> B.
    Variable arg2: B -> C.

    Variable a: A.

    Section CallFunctionWithArgiments.

      (* We can directly pass the arguments to the function...*)
      Eval compute in (f arg1 arg2 a).

    End CallFunctionWithArgiments.

    Section LetBlock.

      (* ... or we can create a sequence of let expression. *)
      Let f := f arg1 arg2.
        ...

      Eval compute in (f a).

    End LetBlock.

  End AnotherSection.

使用第一种方法确实很困难，因为维护此类代码非常困难。如果有五个以上的不同函数，每个函数有4-5个参数，则编写起来会很痛苦。

第二种情况更方便。但是我还有很多额外的“ let”声明行：

   Let f1 := ... 
   Let f2 := ...
      ...
   Let fn := ...

有什么办法可以避免这种多余的样板？理想情况下，我希望Coq只是在上下文中使用类型甚至术语名称来“猜测”正确的参数。

Answer 1

如果上下文（即if，[]等的列表足够简单），则可以使用类型类来不必传递参数。

arg1

Coq：从上下文推论

1 个答案: