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未总结—可变参数的函数与模板

https://songlee24.github.io/2014/07/22/cpp-changeable-parameter/

__VA_ARGS__ https://blog.csdn.net/midion9/article/details/50467909

VA_START VA_END VA_ARG https://blog.csdn.net/weixin_41632560/article/details/82909494