interface 到底是个什么东西？

104359176

这个东西和 Java 的接口似乎不同，既然结构中也能放置函数，为什么要设计 interface 这个东西？

bikong0411

通用数据类型

Godbach

回复 1# 104359176

可以理解为 C 语言中的 void

   

dorodaloo

可以理解为 struct 的 type

1 => int
2 => int

struct1 => interfaceA
struct2 => interfaceA

104359176

回复 4# dorodaloo


    struct 本身就是一种可定义的数据类型，为什么需要 interface.

    哪些地方必须使用 interface, 不能使用 struct

    既然 struct 也能定义方法，为什么还要需要 interface?

dorodaloo

回复 5# 104359176


interface ==> class's type

1. class cat
   
2.     ...
   
3. 
   
4. class dog
   
5.     ...
   
6.    
   
7. c: cat  // c is cat [type cat, class is a type!]
   
8. d: dog  // d's type is dog
   
9. 
   
10. c, d have a different type?? cat vs dog?
    
11. 
    
12. If we have noah's arc [what is all the anim's class?? Off Course! Animal]
    
13. 
    
14. In static lang's container must be have same type! how to do that?
    
15. Give it a interface? [what's interface? So easy! It's a class type ]
    
16. 
    
17. You'll find? cat is animal ==> interfase: Animal
    
18. You'll find? dog is animal ==> interfase: Animal
    
19. 
    
20. What's cat or dog's type?
    
21. OK it is Animal!
    
22. 
    
23. We have A train to the Zoo: (limitations: same types?)
    
24. OK: dog1, dog2,.... (dog1 is a classA, dog2 is a classA....)
    
25. NG: dog1, cat1, dog2,... different type!!
    
26. 
    
27. So? You'll find? tiger? Cat? Dog....they all different type?
    
28. 
    
29. a class is a type: cat , dog, tiger.....
    
30. but an interface A: may be ? cat, dog,...
    
31. So? interface is a class's type!!
    
32. 
    
33. train = cat, dog, tiger, lion, cat....[NO problem, They all have the same type Animal!!]
    
34. That's All

复制代码

dorodaloo

Zoo = Ani1, Ani2,.... {OK} same type
but
Zoo = Cat1, Dog1, Tiger1....{Sorry!! different Type!}


YOU'LL know? WHAT iS an Interface!!

104359176

不太明白。难道 interface 是 struct 更高层次的抽象？

dorodaloo

回复 8# 104359176


    yes, it is. interface ===> class's type

hello_kitty: Cat (type: Cat)
snoopy: Dog (type: Dog)

Boxes = [ hello_kityy, Snoopy ]
Sorry: differnnt type ==> hello_kity, snoopy? [Cat, Dog]

but Boxes = [Animal, Aniaml]  # OK same type all Animal

interface is:

class Cat: Animal
  ...

class Dog: Animal
  ...
hello_kitty: Animal = "hello kitty"
snoopy: Animal = "snoopy"

BOxes = [snoopy, hello_kitty]  #ok, SAME TYPE


var has a type => some class
some class => has a type ==> some interface!!

MMMIX

回复 9# dorodaloo


    Go does not have class.