An object of type stacktrace_entry is either empty, or represents a stacktrace entry and provides operations for querying information about it.

constexpr stacktrace_entry() noexcept;

Postconditions: *this is empty.

constexpr native_handle_type native_handle() const noexcept;

The semantics of this function are implementation-defined.

Remarks: Successive invocations of the native_handle function for an unchanged stacktrace_entry object return identical values.

constexpr explicit operator bool() const noexcept;

Returns: false if and only if *this is empty.

[Note 1:

All the stacktrace_entry query functions treat errors other than memory allocation errors as “no information available” and do not throw in that case.

— end note]

string description() const;

Returns: A description of the evaluation represented by *this, or an empty string.

Throws: bad_alloc if memory for the internal data structures or the resulting string cannot be allocated.

string source_file() const;

Returns: The presumed or actual name of the source file ([cpp.predefined]) that lexically contains the expression or statement whose evaluation is represented by *this, or an empty string.

Throws: bad_alloc if memory for the internal data structures or the resulting string cannot be allocated.

uint_least32_t source_line() const;

Returns: 0, or a 1-based line number that lexically relates to the evaluation represented by *this.

If source_file returns the presumed name of the source file, returns the presumed line number; if source_file returns the actual name of the source file, returns the actual line number.

Throws: bad_alloc if memory for the internal data structures cannot be allocated.

friend constexpr bool operator==(const stacktrace_entry& x, const stacktrace_entry& y) noexcept;

Returns: true if and only if x and y represent the same stacktrace entry or both x and y are empty.