如何在go中调用另一个函数？

i want to call GetUsers from Insert function, but i don't know.

func GetUsers(c echo.Context) error{
  result := models.GetUsers()
  return c.Render(http.StatusOK, "users.html", result)
}

func Insert(c echo.Context) error{
  models.Insert()
  return c.GetUsers()
}

You can call it from Insert simply using GetUsers.

func Insert(c echo.Context) error{
    models.Insert()
    return GetUsers(c)
}

The syntax you used, c.GetUsers() requires GetUsers to be a method declared with Context as its receiver type—in the echo package—a like so:

// package echo
func (c Context) GetUsers() error {
    …
}

// package other
func Insert(c echo.Context) error{
    models.Insert()
    return c.GetUsers()
}

But I am going to assume this is not what you want, since a Context idiomatically should not contain users.