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I just want to verify some rules described at cppreference. It is easy to check, whether expression is lvalue or rvalue.
#include <cassert>
#include <iostream>
template <typename T>
bool IsLValue(const char* i_expression, T&, bool i_expected = true)
{
assert(i_expected);
std::cout << "l_value : " << i_expression << std::endl;
return true;
}
template <typename T>
bool IsLValue(const char* i_expression, T&&, bool i_expected = false)
{
assert(!i_expected);
std::cout << "r_value : " << i_expression << std::endl;
return false;
}
int main()
{
int i = 10;
int* p = &i;
IsLValue("The name of a variable 'i'", i);
IsLValue("The name of a variable 'p'", p);
IsLValue("The name of a function 'main' in scope", main);
IsLValue("The name of a function 'std::cout' in scope", std::cout);
IsLValue("Built-in pre-increment '++i'", ++i);
//etc
return 0;
}
Is there any way to check if expression is xvalue or prvalue?
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