std::type_info::before

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std::type_info

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

Returnstrue if the type of thistype_info precedes the type ofrhs in the implementation's collation order. No guarantees are given; in particular, the collation order can change between the invocations of the same program.

[edit]Parameters

rhs

another type information object to compare to

[edit]Return value

true if the type of thistype_info precedes the type ofrhs in the implementation's collation order.

[edit]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";elsestd::cout<<"char goes before int in this implementation.\n";}

Possible output:

char goes before int in this implementation.

[edit]See also

operator==operator!=

(removed in C++20)

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

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