25 lines
450 B
Markdown
25 lines
450 B
Markdown
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# function 包装器
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提供更加一致的接口，避免多次实例化
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对于调用特征标(call signature)一样的函数，使用function进行包装
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```cpp
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std::function<double(int)> fun1;
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```
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+ 可接受任何函数指针，函数对象，lambda表达式
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```cpp
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template <typename T>
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void print(T f, int a) {
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std::cout << f(a) << std::endl;
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}
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double f1(int a) {
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return a/1.0;
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}
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std::function<double(int)> fun1=f1;
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print(fun1, 10);
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```
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