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  1. #include <iostream>
  2. using namespace std;
  3.  
  4. class Tensor
  5. {
  6. public:
  7. 	Tensor& setA() { cout << "A"; return *this; }
  8.     Tensor& setB() { cout << "B"; return *this; }
  9.     Tensor& setC() { cout << "C"; return *this; }
  10.     Tensor& setD() { cout << "D"; return *this; }
  11.     Tensor& setE() { cout << "E"; return *this; }
  12.     void build() { cout << endl; }
  13. };
  14.  
  15. Tensor& doSetE(Tensor &t)
  16. {
  17. 	return t.setE();
  18. }
  19.  
  20. Tensor& doNoOp(Tensor &t)
  21. {
  22. 	return t;
  23. }
  24.  
  25. void doTest(bool flag)
  26. {
  27. 	Tensor& (*temp)(Tensor&) = flag ? &doSetE : &doNoOp;
  28.  
  29.     temp(Tensor{}
  30.     .setA()
  31.     .setB()
  32.     .setC()
  33.     .setD())
  34.     .build();
  35. }
  36.  
  37. int main()
  38. {
  39. 	doTest(false);
  40. 	doTest(true);
  41. 	return 0;
  42. }
Success #stdin #stdout 0.01s 5372KB
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stdin
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Standard input is empty
stdout
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ABCD
ABCDE
https://ideone.com/WQzHvc
language:
C++ (gcc 8.3)
created:
4 years ago
visibility:
public

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