std::type_info::before

 

C++

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integral_constantbool_constanttrue_typefalse_type (C++11)(C++17)(C++11)(C++11)
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conjunction (C++17)
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negation (C++17)

Supported operations
is_constructibleis_trivially_constructibleis_nothrow_constructible (C++11)(C++11)(C++11)
is_default_constructibleis_trivially_default_constructibleis_nothrow_default_constructible (C++11)(C++11)(C++11)
is_copy_constructibleis_trivially_copy_constructibleis_nothrow_copy_constructible (C++11)(C++11)(C++11)
is_move_constructibleis_trivially_move_constructibleis_nothrow_move_constructible (C++11)(C++11)(C++11)
is_assignableis_trivially_assignableis_nothrow_assignable (C++11)(C++11)(C++11)
is_copy_assignableis_trivially_copy_assignableis_nothrow_copy_assignable (C++11)(C++11)(C++11)
is_move_assignableis_trivially_move_assignableis_nothrow_move_assignable (C++11)(C++11)(C++11)
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has_virtual_destructor (C++11)
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Type transformations
aligned_storage (C++11) aligned_union (C++11) decay (C++11) enable_if (C++11) void_t (C++17)	conditional (C++11) common_type (C++11) underlying_type (C++11) result_of (C++11)

 

std::type_info

Member functions

type_info::~type_info

type_info::operator==type_info::operator!=

type_info::before

type_info::hash_code (C++11)

type_info::name

 

bool before( const type_info& rhs );

Returns true if the referred type precedes type, referred to by 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 referred type precedes type, referred to by 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!=

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