std::type_info::before

 

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type_info::before

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bool before( const type_info& rhs ) const;		(noexcept since C++11)

Returns true if the type of this type_info precedes the type of rhs in the implementation's collation order. No guarantees are given; in particular, the collation order can change between the invocations of the same program.

Parameters

rhs

-

another type information object to compare to

Return value

true if the type of this type_info precedes the type of rhs in the implementation's collation order.

Example

Run this code

#include <iostream>
#include <typeinfo>

int main()
{
    if (typeid(int).before(typeid(char)))
        std::cout << "int goes before char in this implementation.\n";
    else
        std::cout << "char goes before int in this implementation.\n";
}

Possible output:

char goes before int in this implementation.

See also

operator==operator!= (removed in C++20)

checks whether the objects refer to the same type (public member function)