I am experimenting with function pointers and lambdas in C++ and my function definitions are as follows -
float max(float a, float b){
std::cout<<"In float max"<<std::endl;
return (a > b) ? a : b;
}
int max(int a, int b){
std::cout<<"In Int max"<<std::endl;
return (a > b) ? a : b;
}
template<typename type1, typename type2>
int compareNumber(type1 a, type1 b, type2 function){
return function(a, b);
}
and from my main function, I am calling it as follows -
int main(){
std::cout<<compareNumber<float, float (float, float )>(5.2542f, 2.314f, max)<<std::endl;
std::cout<<compareNumber<float>(1.3467f, 2.6721f, [=](float a, float b){
return (a > b) ? a:b;
})<<std::endl;
std::cout<<max(5.3f, 2.7f)<<std::endl;
std::cout<<max(1, 2)<<std::endl;
}
The Issue is that, If I simply invoke the function separately, the correct values get returned, but when using a lambda function or a function pointer, the values get cast to int for reasons I am not able to point out.
Here Is my output -
In float max
5
2
In float max
5.3
In Int max
2
I checked the output type of the output and it indeed is an integer. I had checked it as follows -
std::cout<<std::is_same<int, decltype(compareNumber<float, float (float, float )>(5.2542f, 2.314f, max))>()<<std::endl;
The above code snippet prints 1.
Could anyone please tell me as to what exactly is happening here?.
TIA
PS - I just realized that the return type is int
and not type1
and had posted the question without thinking much and in a hurry. Sorry for the trivial question
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