std::error_category::error_category

std::error_category::error_category - cppreference.com

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Utilities library

Language support

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three_way_comparablethree_way_comparable_with

(C++20)(C++20)

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(C++20)

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(C++20)

partial_ordering

(C++20)

common_comparison_category

(C++20)

compare_three_way_result

(C++20)

(C++20)

(C++20)

(C++20)

(C++20)

compare_strong_order_fallback

(C++20)

compare_weak_order_fallback

(C++20)

compare_partial_order_fallback

(C++20)

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cmp_equalcmp_lesscmp_less_than

(C++20)(C++20)(C++20)

cmp_not_equalcmp_greatercmp_greater_than

(C++20)(C++20)(C++20)

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(C++20)

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Common vocabulary types

pair
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tuple_size (C++11)
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expected (C++23)

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Diagnostics library

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exception
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exception_ptr (C++11)
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logic_error
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System error
error_category (C++11)
generic_category (C++11)
system_category (C++11)
error_condition (C++11)
errc (C++11)
error_code (C++11)
system_error (C++11)
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basic_stacktrace (C++23)
Debugging support
is_debugger_present (C++26)
breakpoint_if_debugging (C++26)
breakpoint (C++26)

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std::error_category

Member functions
error_category::error_category
error_category::~error_category
error_category::name
error_category::default_error_condition
error_category::equivalent
error_category::message
error_category::operator==error_category::operator!=error_category::operator<error_category::operator<=> (until C++20)(until C++20)(C++20)

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`constexpr error_category() noexcept;`	(1)	(since C++11)
`error_category( const error_category& ) = delete;`	(2)	(since C++11)

1) Constructs the error category object.

2) Copy constructor is deleted. error_category is neither MoveConstructible nor CopyConstructible.

Parameters

(none)

Defect reports

The following behavior-changing defect reports were applied retroactively to previously published C++ standards.

DR	Applied to	Behavior as published	Correct behavior
LWG 2145	C++11	`error_category` was not constructible	default constructor added