c++如何实现这样的一个宏定义 - V2EX
xuyaomin
V2EX    C++

c++如何实现这样的一个宏定义

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  •   xuyaomin Oct 15, 2019 5460 views
    This topic created in 2424 days ago, the information mentioned may be changed or developed.

    请问怎么定义一个宏实现下面的效果 输入 mc(t, a, b)扩展为 t_a t_b,要求参数是可变的 //mc(t, a, b) //t_a //t_b

    //mc(t, a, b, c) //t_a //t_b //t_c 
    4 replies    2019-10-16 11:07:57 +08:00
    ipwx
        1
    ipwx  
       Oct 15, 2019
    https://codecraft.co/2014/11/25/variadic-macros-tricks/

    虽然我觉得整这么复杂没意义
    lechain
        2
    lechain  
       Oct 16, 2019 via Android
    ##
    augustheart
        3
    augustheart  
       Oct 16, 2019
    可变参的宏 gcc 支持,vc 不支持。
    vc 要支持的话就是定义不同个数的参数形式咯
    across
        4
    across  
       Oct 16, 2019   1
    上面说的差不多了,其实就是

    #define mc(t,a,b) t##a t##b

    写 mc(Class, Example,Inst) 就实现你要的了,至于参数可变的这个就复杂了,我看大部分例子都是预先写好版本,最多 10 来个参数够你用了吧。这种宏在大型项里还是挺多的
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