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std::type_info::before

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

#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

(removed in C++20)
checks whether the objects refer to the same type
(public member function)

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