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  1. /*****************************************************************
  2. Name : 
  3. Date : 2017/04/04
  4. By   : CharlotteHonG
  5. Final: 2017/04/04
  6. *****************************************************************/
  7. #include <iostream>
  8. using namespace std;
  9.  
  10. template<class T, class T2>
  11. auto fun1(T a,  T2 b) -> decltype(a+b){
  12.     return a+b;
  13. }
  14.  
  15. template<class T, class T2>
  16. auto fun2(T a,  T2 b){
  17.     return a+b;
  18. }
  19.  
  20. template<class T, class T2>
  21. decltype(auto) fun3(T a,  T2 b){
  22.     return a+b;
  23. }
  24.  
  25.  
  26. /*==============================================================*/
  27. int main(int argc, char const *argv[]){
  28.     cout << "fun=" << fun1(1, 1.5) << endl;
  29.     cout << "fun=" << fun2(1, 1.5) << endl;
  30.     cout << "fun=" << fun3(1, 1.5) << endl;
  31.  
  32.     return 0;
  33. }
  34. /*==============================================================*/
Success #stdin #stdout 0s 16064KB
comments (?)
stdin
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Standard input is empty
stdout
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fun=2.5
fun=2.5
fun=2.5
https://ideone.com/nHiXmH
問題｜decltype(auto) 用法的差異
language:
C++14 (gcc 8.3)
created:
8 years ago
visibility:
public

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