std::type_info::before

 

C++

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Utilities library

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bitset

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rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=

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optional

any

variant

in_placein_place_typein_place_indexin_place_tin_place_type_tin_place_index_t

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ptrdiff_t size_t max_align_t (C++11) byte (C++17)	nullptr_t (C++11) offsetof NULL
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C numeric limits interface
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type_info type_index (C++11)	bad_typeid bad_cast
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is_reference (C++11)
is_lvalue_reference (C++11)
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is_member_pointer (C++11)
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is_member_function_pointer (C++11)

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has_unique_object_representations (C++17)
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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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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)
is_destructibleis_trivially_destructibleis_nothrow_destructible (C++11)(C++11)(C++11)
has_virtual_destructor (C++11)
is_swappable_withis_swappableis_nothrow_swappable_withis_nothrow_swappable (C++17)(C++17)(C++17)(C++17)
Relationships and property queries
is_same (C++11) is_base_of (C++11) is_convertible (C++11)	alignment_of (C++11) rank (C++11) extent (C++11)
is_invocableis_invocable_ris_nothrow_invocableis_nothrow_invocable_r (C++17)(C++17)(C++17)(C++17)
Type modifications
remove_cvremove_constremove_volatile (C++11)(C++11)(C++11) add_cvadd_constadd_volatile (C++11)(C++11)(C++11) make_signed (C++11) make_unsigned (C++11)	remove_reference (C++11) add_lvalue_referenceadd_rvalue_reference (C++11)(C++11) remove_pointer (C++11) add_pointer (C++11) remove_extent (C++11) remove_all_extents (C++11)
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_ofinvoke_result (C++11)(deprecated in C++17)(C++17)

 

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 ) const;

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!=

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