Standard library header <contracts> (C++26)

 

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Language support <cfloat> <climits> <compare> (C++20) <contracts> (C++26) <coroutine> (C++20) <csetjmp> <csignal> <cstdarg> <cstddef> <cstdint> (C++11) <cstdlib> <exception> <initializer_list> (C++11)    <limits> <new> <source_location> (C++20) <stdfloat> (C++23) <typeinfo> <version> (C++20) Concepts <concepts> (C++20) Diagnostics <cassert> <cerrno> <debugging> (C++26) <stacktrace> (C++23) <stdexcept> <system_error> (C++11) Memory management <memory> <memory_resource> (C++17) <scoped_allocator> (C++11) Metaprogramming <type_traits> (C++11) <ratio> (C++11)

General utilities <any> (C++17) <bitset> <bit> (C++20) <charconv> (C++17) <expected> (C++23) <format> (C++20) <functional> <optional> (C++17) <stdbit.h> (C++26) <tuple> (C++11) <typeindex> (C++11) <utility> <variant> (C++17) Containers <array> (C++11) <deque> <flat_map> (C++23) <flat_set> (C++23) <forward_list> (C++11) <hive> (C++26) <inplace_vector> (C++26)    <list> <map> <mdspan> (C++23) <queue> <set> <span> (C++20) <stack> <unordered_map> (C++11) <unordered_set> (C++11) <vector> Iterators <iterator> Ranges <generator> (C++23) <ranges> (C++20)

Algorithms <algorithm> <numeric> Strings <cctype> <cstring> <cuchar> (C++11) <cwchar> <cwctype> <string_view> (C++17) <string> Text processing <clocale> <codecvt> (C++11/17/26*) <locale> <regex> (C++11) <text_encoding> (C++26)    Numerics <cfenv> (C++11) <cmath> <complex> <linalg> (C++26) <numbers> (C++20) <random> (C++11) <simd> (C++26) <stdckdint.h> (C++26) <valarray> Time <chrono> (C++11) <ctime> C compatibility <ccomplex> (C++11/17/20*) <ciso646> (until C++20) <cstdalign> (C++11/17/20*) <cstdbool> (C++11/17/20*) <ctgmath> (C++11/17/20*)

Input/output <cinttypes> (C++11) <cstdio> <filesystem> (C++17) <fstream> <iomanip> <iosfwd> <iostream> <ios> <istream> <ostream> <print> (C++23) <spanstream> (C++23) <sstream> <streambuf> <strstream> (C++98/26*) <syncstream> (C++20) Concurrency support <atomic> (C++11) <barrier> (C++20) <condition_variable> (C++11) <future> (C++11) <hazard_pointer> (C++26) <latch> (C++20) <mutex> (C++11) <rcu> (C++26) <semaphore> (C++20) <shared_mutex> (C++14) <stdatomic.h> (C++23) <stop_token> (C++20) <thread> (C++11) Execution support <execution> (C++17)

 

This header is part of the language support library.

Types
Defined in namespace std::contracts
assertion_kind (C++26)	the kind of the contract assertion violated (enum)
evaluation_semantic (C++26)	the evaluation semantic when the contract violation occurs (enum)
detection_mode (C++26)	the reason that causes the contract violation (enum)
contract_violation (C++26)	the type holding the contract-violation information (class)
Functions
Defined in namespace std::contracts
invoke_default_contract_violation_handler (C++26)	invokes the default contract-violation handler (function)

Synopsis

// all freestanding
namespace std::contracts {

  enum class assertion_kind : /* unspecified */ {
    pre = 1,
    post = 2,
    assert = 3
  };
  
  enum class evaluation_semantic : /* unspecified */ {
    ignore = 1,
    observe = 2,
    enforce = 3,
    quick_enforce = 4
  };
 
  enum class detection_mode : /* unspecified */ {
    predicate_false = 1,
    evaluation_exception = 2
  };

  // class contract_violation
  class contract_violation;

  void invoke_default_contract_violation_handler(const contract_violation&);
}

Class std::contracts::contract_violation

namespace std::contracts {
  class contract_violation
  {
    // no user−accessible constructor
  public:
    contract_violation(const contract_violation&) = delete;
    contract_violation& operator=(const contract_violation&) = delete;
    /* see description */ ~contract_violation();
    const char* comment() const noexcept;
    contracts::detection_mode detection_mode() const noexcept;
    exception_ptr evaluation_exception() const noexcept;
    bool is_terminating() const noexcept;
    assertion_kind kind() const noexcept;
    source_location location() const noexcept;
    evaluation_semantic semantic() const noexcept;
  };
}