Implizite und Explizite Typspezifikation

              
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#include <iostream>

template<typename T>
void PrintValue(T value) { std::cout << value << std::endl; }
// The compiler assigns the type for `T` 
// Based on the type of the passed argument `value`

int main() 
{
    PrintValue(42);         // `T` is deduced as `int`
    PrintValue(3.14);       // `T` is deduced as `double`
    PrintValue("Hello");    // `T` is deduced as `const char*`
}

              
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#include <iostream>

int main()
{
	int a = 300;
	int b = 200;

    // `std::swap` is actually a template and you can prove it
    // Try to specify `int` type explicitly `std::swap<int>`
	std::swap(a, b);
    std::cout << a << " " << b << std::endl;
}

              
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#include <iostream>

template<typename T>
T GetDefaultValueSum(T a, T b) { return a + b; }

int main() 
{
    // If `float` won't be specified, this code would generate an error
    std::cout << GetDefaultValueSum<float>(2, 2.5) << std::endl;
}