The class template basic_stacktrace satisfies the requirements of a reversible container ([container.rev.reqmts]), of an allocator-aware container ([container.alloc.reqmts]), and of a sequence container ([sequence.reqmts]), except that

• only move, assignment, swap, and operations defined for const-qualified sequence containers are supported and,
• the semantics of comparison functions are different from those required for a container.

static basic_stacktrace current(const allocator_type& alloc = allocator_type()) noexcept;

static basic_stacktrace current(size_type skip, const allocator_type& alloc = allocator_type()) noexcept;

Let t be a stacktrace as-if obtained via basic_stacktrace​::​current(alloc).

Let n be t.size().

Returns: A basic_stacktrace object where frames_ is direct-non-list-initialized from arguments t.begin() + min(n, skip), t.end(), and alloc, or an empty basic_stacktrace object if the initialization of frames_ failed.

static basic_stacktrace current(size_type skip, size_type max_depth, const allocator_type& alloc = allocator_type()) noexcept;

Let t be a stacktrace as-if obtained via basic_stacktrace​::​current(alloc).

Let n be t.size().

Hardened preconditions: skip <= skip + max_depth is true.

Returns: A basic_stacktrace object where frames_ is direct-non-list-initialized from arguments t.begin() + min(n, skip), t.begin() + min(n, skip + max_depth), and alloc, or an empty basic_stacktrace object if the initialization of frames_ failed.

basic_stacktrace() noexcept(is_nothrow_default_constructible_v<allocator_type>);

Postconditions: empty() is true.

explicit basic_stacktrace(const allocator_type& alloc) noexcept;

Effects: alloc is passed to the frames_ constructor.

Postconditions: empty() is true.

basic_stacktrace(const basic_stacktrace& other); basic_stacktrace(const basic_stacktrace& other, const allocator_type& alloc); basic_stacktrace(basic_stacktrace&& other, const allocator_type& alloc); basic_stacktrace& operator=(const basic_stacktrace& other); basic_stacktrace& operator=(basic_stacktrace&& other) noexcept(allocator_traits<Allocator>::propagate_on_container_move_assignment::value || allocator_traits<Allocator>::is_always_equal::value);

Remarks: Implementations may strengthen the exception specification for these functions ([res.on.exception.handling]) by ensuring that empty() is true on failed allocation.

using const_iterator = implementation-defined;

allocator_type get_allocator() const noexcept;

Returns: frames_.get_allocator().

const_iterator begin() const noexcept; const_iterator cbegin() const noexcept;

Returns: An iterator referring to the first element in frames_.

If empty() is true, then it returns the same value as end().

const_iterator end() const noexcept; const_iterator cend() const noexcept;

Returns: The end iterator.

const_reverse_iterator rbegin() const noexcept; const_reverse_iterator crbegin() const noexcept;

Returns: reverse_iterator(cend()).

const_reverse_iterator rend() const noexcept; const_reverse_iterator crend() const noexcept;

Returns: reverse_iterator(cbegin()).

bool empty() const noexcept;

Returns: frames_.empty().

size_type size() const noexcept;

size_type max_size() const noexcept;

Returns: frames_.max_size().

const_reference operator[](size_type frame_no) const;

Hardened preconditions: frame_no < size() is true.

Returns: frames_[frame_no].

const_reference at(size_type frame_no) const;

Returns: frames_[frame_no].

Throws: out_of_range if frame_no >= size().

template<class Allocator2> friend bool operator==(const basic_stacktrace& x, const basic_stacktrace<Allocator2>& y) noexcept;

Returns: equal(x.begin(), x.end(), y.begin(), y.end()).

template<class Allocator2> friend strong_ordering operator<=>(const basic_stacktrace& x, const basic_stacktrace<Allocator2>& y) noexcept;

Returns: x.size() <=> y.size() if x.size() != y.size(); lexicographical_compare_three_way(x.begin(), x.end(), y.begin(), y.end()) otherwise.

void swap(basic_stacktrace& other) noexcept(allocator_traits<Allocator>::propagate_on_container_swap::value || allocator_traits<Allocator>::is_always_equal::value);

Effects: Exchanges the contents of *this and other.

template<class Allocator> void swap(basic_stacktrace<Allocator>& a, basic_stacktrace<Allocator>& b) noexcept(noexcept(a.swap(b)));

Effects: Equivalent to a.swap(b).

string to_string(const stacktrace_entry& f);

Returns: A string with a description of f.

Recommended practice: The description should provide information about the contained evaluation, including information from f.source_file() and f.source_line().

template<class Allocator> string to_string(const basic_stacktrace<Allocator>& st);

Returns: A string with a description of st.

ostream& operator<<(ostream& os, const stacktrace_entry& f);

Effects: Equivalent to: return os << to_string(f);

template<class Allocator> ostream& operator<<(ostream& os, const basic_stacktrace<Allocator>& st);

Effects: Equivalent to: return os << to_string(st);