* Fix generic path format when formatting to wide strings
get_path_string used the native or generic string computed by the path
formatter only when converting wchar_t to UTF-8 and fell back to
p.string<Char>() otherwise, so the 'g' specifier was ignored when the
output character type matched path::value_type. On Windows,
fmt::format(L"{:g}", path(L"C:\\foo")) returned L"C:\\foo" instead of
L"C:/foo". Use the passed string in that case, as write_escaped_path
already does.
* Keep generic path format when converting to wide strings on POSIX
Treat a leading '0' as the zero flag rather than the start of the width so
it is rejected (as in the core formatter) instead of being silently consumed.
Also trim the exception_align test to the cases this actually introduces.
* Support width and alignment in std::exception formatter
The formatter for std::exception (and std::exception_ptr) previously
accepted only the optional 't' type-name specifier, so standard fill,
align and width specifiers were rejected with "unknown format
specifier". This made it impossible to pad or align exception messages,
e.g. when laying them out in a log column.
Parse the standard fill/align/width specifiers (as the std::filesystem::
path formatter already does) and apply them when writing the message.
Dynamic width ({:{}}) and the 'none'/'unknown exception' cases for
exception_ptr are handled too. Existing behavior ({}, {:t}, nested
exception unwinding) is unchanged.
* Update std.h
Detect when a std::exception also derives from std::nested_exception
(e.g. via std::throw_with_nested) and unwind the whole chain, joining
each level with ": ". The type-name flag ({:t}) is honored at every
level, and the std::exception_ptr formatter inherits this behavior.
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
In some cases, people might want to format the std::unexpected type itself,
independent of the value type, this commit makes it possible.
Co-authored-by: Robin Oger <robin.oger.work@gmail.com>
Formatting a std::optional<T> where T had a custom format_as(T) function failed to compile with clang,
due to set_debug_format being hidden by private inheritance. This fix makes the function available through a using clause.
* fix: make std::bitset formattable again
It used to be formattable via operator<<(ostream&) implicitly. Make it
formattable again, but this time via formatter specialization.
* fix: make nested_formatter constexpr default constructible
