Changelog
3.0.2
Released 2024-xx-xx
- Fix formatting options of user-defined types sometimes being ignored
- Update documentation to have a version-dropdown
3.0.1
Released 2024-06-15
- Bump
SOVERSION
to 3. (reported in #117, thanks @xvitaly (Vitaly)) - Call
find_package
in CMake iff a target is not already defined (reported in #118, thanks @ajtribick) - Remove
find_dependency(Threads)
fromscn-config.cmake
3.0.0
Released 2024-06-08
Breaking changes
- The default behavior for scanning integers is now
d
(decimal) instead ofi
(detect base from prefix).
// v3 auto result = scn::scan<int>("077", "{}"); // result->value() == 77 result = scn::scan<int>("078", "{}"); // result->value() == 78 // v2 auto result = scn::scan<int>("077", "{}"); // result->value() == 63 result = scn::scan<int>("078", "{}"); // result->value() == 7 // result->range() == "8" // (Because of the '0' prefix, an octal number is expected, // and '8' is not a valid octal digit, so reading is stopped)
- A large part of the bundled
<ranges>
-implementation is removed. Only the parts strictly needed for the library are included.- The library no longer uses a stdlib provided
<ranges>
, even if available. - This cut down compile times massively for library consumers
- You now may need to specialize
scn::ranges::enable_borrowed_range
for your own range types, even if you've already specializedstd::ranges::enable_borrowed_range
. Specializations ofstd::
are already borrowed out of the box.basic_string_view
- The library no longer uses a stdlib provided
// std::span is a borrowed_range, // but scnlib doesn't know about it auto result = scn::scan<...>(std::span{...}, ...); // decltype(result->range()) is scn::ranges::dangling namespace scn::ranges { template <typename T, size_t E> inline constexpr bool enable_borrowed_range<std::span<T, E>> = true; } auto result = scn::scan<...>(std::span{...}, ...); // decltype(result->range()) is a scn::ranges::subrange<const T*>
scn::span
is removedscan_arg_store
andborrowed_subrange_with_sentinel
are removed from the public interfacescan_arg_store
is changed to be non-copyable and non-movable, for correctness reasons (it holds references to itself, copying and moving would be needlessly expensive)- The interface of
make_scan_result
is changed to take atuple
instead of the now unmovablescan_arg_store
.
// v3 auto args = make_scan_args<scan_context, Args...>(); auto result = vscan(source, format, args); return make_scan_result(std::move(result), std::move(args.args())); // v2 auto args = make_scan_args<scan_context, Args...>(); auto result = vscan(source, format, args); return make_scan_result(std::move(result), std::move(args));
- The meaning of the "width" field in format specifiers is changed to mean the minimum field width (like in
std::
), instead of the maximum (sort of like informat scanf
)
// v3 auto result = std::scan<int>("123", "{:2}"); // result->value() == 123 // result->range() == "" // v2 auto result = std::scan<int>("123", "{:2}"); // result->value() == 12 // result->range() == "3"
Features
- The "precision" field is added as a format specifier, which specifies the maximum fields width to scan (like in
std::
)format
// Scan up to 2 width units auto result = scn::scan<int>("123", "{:.2}"); // result->value() == 12 // result->range() == "3"
- Support for field fill and alignment is added. This interacts well with the new width and precision fields
// Read an integer, aligned to the right ('>'), with asterisks ('*') auto result = std::scan<int>("***42", "{:*>}"); // result->value() == 42 // result->range() == "" // Read an integer, aligned to the left ('<'), with whitespace (default), // with a maximum total width of 3 auto result = std::scan<int>("42 ", "{:<.3}"); // result->value() == 42 // result->range() == " "
- In general, there seems to be a ~10% to 20% improvement in run-time performance.
Changes
- The dependency on
simdutf
is removed. The library now has no external dependencies to compiled libraries (FastFloat, an internal dependency, is a header-only library) - The number of source files is dramatically decreased: there are now just the public headers, a private implementation header, and a private implementation source file. This cuts down the time needed to compile the library, and any user code including it to a half (yes, really!)
Fixes
- Fix skipping of multiple characters of whitespace in the format string (reported in #116, thanks @Jonathan-Greve (Jonathan Bjørn Greve))
2.0.3
Released 2024-05-19
Fixes
- Fix documentation: default format type specifier for integers is
i
, notd
: when not explicitly specified by a format specifier, the base of an integer is determined based on its prefix:0x...
is hexadecimal,0...
or0o...
is octal,0b...
is binary, and everything else is decimal. - Fix a compilation error which would occur when scanning more than 11 arguments with
scn::
.scan - Small CMake adjustments to better support use as a subproject (#113, thanks @frankmiller (Frank Miller))
- Fix misplaced include of
GNUInstallDirs
in CMake (#111, thanks @WangWeiLin-MV) - Allow for externally installed versions for GTest and Google Benchmark (#112, thanks @xvitaly (Vitaly))
- Adjust the definition of
SCN_COMPILER
to fix usage with a recent Clang using modules (#109, thanks @Delta-dev-99 (Armando Martin)) - Allow for more versions of dependencies (simdutf, fast_float)
- Fix C++23 build failure caused by missing inclusion of
<utility>
forstd::unreachable
2.0.2
Released 2024-02-19
Fixes
- Fix segfault when runtime-parsing
{:[^
as a format string. - Fix compilation of
scan_buffer.cpp
on some MSVC versions. - Remove stray
test/
folder
2.0.1
Released 2024-02-12
Fixes
- Fix detection of support for
std::regex_constants::multiline
(#98, thanks @jiayuehua (Jia Yue Hua)) - Fix builds of
float_reader
on Android SDK < v28 (#99, thanks @jiayuehua (Jia Yue Hua)) - Fix typo in README example (#100, thanks @ednolan (Eddie Nolan))
2.0.0
Released 2024-01-19
Changes are in comparison to 2.0.0-beta.
Features
- Regular expression scanning in
<scn/regex.h>
- Scanning of
FILE*
s. - Faster integer scanning with
scn::
scan_int - Allow disabling support for:
- Specific types (
SCN_DISABLE_TYPE_*
) - Locales (
SCN_DISABLE_LOCALE
) - IOStreams (
SCN_DISABLE_IOSTREAM
) - Regex support (
SCN_DISABLE_REGEX
) - Floating-point scanning fallbacks (
SCN_DISABLE_FROM_CHARS
,SCN_DISABLE_STRTOD
) - These can be useful in some constrained environments, where these facilities are either not available or not used
- Thanks @cjvaughter (CJ Vaughter) for the original implementation in v1 in #70 and #71
- Specific types (
Changes
scn::basic_istreambuf_view
removed.- Sort-of replaced by being able to scan from
FILE
s.
- Sort-of replaced by being able to scan from
scn::basic_erased_range
andscn::basic_caching_view
removed.- Replaced by library-internal
scn::detail::basic_scan_buffer
.
- Replaced by library-internal
- String scanners now require valid Unicode as input, and don't spew out garbage when given some.
- Specifiers like
:alpha:
and\w
removed from[character set]
matching. Use regular expressions instead, or explicitly state the character range (likea-zA-Z
for:alpha:
). scn::runtime
renamed toscn::
.runtime_format
Fixes and small changes
- Update implementation of
scn::span
- Fix handling of literal space characters in format strings
- Add
COMPONENT
values to CMake install targets - Default to Release-builds in CMake if no
CMAKE_BUILD_TYPE
is set, and we're the top project (see #89, thanks @ldeng-ustc (Long Deng) for the idea) - Add install destination for shared libraries (thanks @uilianries (Uilian Ries))
2.0.0-beta
Released 2023-10-29
Major overhaul, both internally and in terms of the library interface. The library is rewritten in its entirety. See the documentation (note the new URL: https:/
This is a beta pre-release. There may still be some bugs. Changes before v2.0.0 proper are possible, but aren't probably going to be major.
Major changes include:
- C++17 is required.
- Several names are changed to include the
scan_
prefix. scn::
returns the scanned values by value. Output parameters are no longer used.scan scn::
now accepts allscan forward_range
s (v1:bidirectional_range
+ default- and move constructible).scn::
returns a view (scan subrange
) into its input, and never takes ownership.- Scope is more focused: list operations,
ignore
,getline
, andfile
have been removed. - Performance improvements
- Completely reworked internals
1.1.3
Released 2023-11-05
Expected to be the last release in the v1-branch. Development efforts are now fully directed towards v2.
Features
- Allow disabling support for individual types with
SCN_DISABLE_TYPE_*
(#70, thanks @cjvaughter (CJ Vaughter))- Also, allow for disabling the fallbacks to
std::
andfrom_chars std::
when scanning floatsstrtod - This provides possible binary size reductions, and allows better use in e.g. embedded platforms
- Also, allow for disabling the fallbacks to
- Allow disabling runtime localization with
SCN_DISABLE_LOCALE
(#71, thanks @cjvaughter (CJ Vaughter)) - Parse leading
+
signs in floats (reported in #77)
Fixes
- Fix
scn::wrap(std::string_view&&)
being ambiguous on gcc (reported in #83) - Fix compiler error in
scn::basic_string_view<CharT>::substr
(reported in #86) - Fix memory safety issues found with ASan and UBsan in
small_vector
,detail::utf16::validate_next
, anddetail::get_buffer
. - Add
COMPONENT
to CMake install targets (#80, thanks @pawelwod) - Fix calculation of
SCN_MSVC
from_MSC_FULL_VER
(#62, thanks @matbech (Mathias Berchtold)) - Fix MSVC
C4146
warning ininteger_scanner
(#64, thanks @matbech (Mathias Berchtold)) - Use
if constexpr
andstd::unreachable
if available (#61, #78, thanks @matbech (Mathias Berchtold)) - Improve error messages given from the float parser
1.1.2
Released 2022-03-19
- Change
SCN_VERSION
to report the correct version number: 1.1.0 -> 1.1.2 (#57)
1.1.1
Released 2022-03-16
- Fix issue with values being skipped when using files and
file.sync()
(#56)- Every call to
file.sync()
needs to be accompanied by a call toreset_begin_iterator()
to the result object - This is a temporary fix, permanent fix coming in v2.0.0
- Every call to
int i; auto ret = scn::scan(scn::cstdin(), "{}", i); scn::cstdin().sync(); ret.range().reset_begin_iterator(); // Not necessary with input and prompt ret = scn::input("{}", i);
1.1
Released 2022-03-12
- Add support for scanning 8-bit integers (
(un)signed char
,(u)int8_t
), and characters (char
,wchar_t
) as integers
int8_t i1, i2; char c1, c2; auto ret = scn::scan("1 2 3 4", "{} {:c} {} {:i}", i1, i2, i3, i4); // ret == true // i1 == 1 // i2 == '2' // c1 == '3' // c2 == 4
1.0
Released 2022-02-28
- Fix bugs
- Reorganize and expand fuzzing, making it oss-fuzz ready
- Expand test suite with more localized tests
- Update benchmark results
- Update submodules
1.0-rc1
Released 2022-02-21
Additions
- Unicode support
- Ranges and format strings are assumed to be UTF-8 (narrow), UTF-16 (wide, Windows), or UTF-32 (wide, POSIX), regardless of locale
- Add
scn::code_point
, which can be passed as a delimeter toscn::getline
,scn::scan_list
and others - Locales rewritten
- Add
lemire/fast_float
as a dependency, and use it for parsing floats if possible - Add
scn::scan_usertype
andscn::vscan_usertype
- Add
<scn/fwd.h>
header file
Changes
- Redesigned format strings
- Alignment, fill, width flags
- Position-dependent
L
- Reworked integer and float parsing flags (new defaults)
- String set parsing
- Add
scn::common_parser
- Redesigned whitespace skipping
scn::buffer_scanner
->scn::span_scanner
, spans are more like strings now when scanned- Massive folder and file reorganization
- Rewritten list scanning
result::string_view()
,::span()
,::string()
->result::range_as_*()
read_char()
->read_code_unit()
- Decrease generated code sizes by redesigning vscan, and adding more vscan definitions
- Move
scn::wrap
to the public interface - Add
scn::make_args_for
,scn::make_context
, andscn::make_parse_context
- Move
[[nodiscard]]
added where necessary
Fixes and minor stuff
- Update bloat benchmarks
- Add a lot more tests
- Update GitHub workflows: add gcc11, clang12, msvc2022, gcc on macOS, and Alpine, remove clang9
- Radically increase fuzzing coverage, fix bugs found with it
- Fix typo in README example (#41, #44, thanks @andreasbuykx (Andreas Buykx) and @phoebe-leong)
- Fix leftover typo in docs/guide (#49, thanks @danra (Dan Raviv))
- New .clang-format file
- Tweaks to README badges
- Update submodules
- Numerous bug fixes
0.4
Released 2020-11-13
Changes and removals
- Rework source range handling:
- Non-views are now accepted as source ranges – this includes types like
std::
andstring std::
vector<char> - Non-reconstructible ranges are now also accepted – scanning functions no longer return a reconstructed source range. The member function
.range()
can be used to scan the range again, and.reconstruct()
reconstructs the range, if possible. Other helper member functions are also available. - Source ranges are now either taken by const lvalue reference or rvalue reference, so they are no longer modified by scanning functions. To access the leftover range, use the return value of the scanning function.
- Non-views are now accepted as source ranges – this includes types like
- Rewrite file handling, with hopefully way less bugs this time around
- Remove
file_view
and caching ranges - Move memory mapped files to the public API
- Remove
- Remove
default_tag
, replace withscan_default
function template - Remove support for
scanf
syntax, includingscn::scanf
andscn::basic_scanf_parse_context
. - Improve Ranges integration:
- Move custom Ranges implementation to the public API (out from
scn::detail::ranges
):scn::custom_ranges
- Integrate standard library Ranges, if available:
scn::std_ranges
aliased tostd::
ranges - Use stdlib Ranges, if available, fall back to custom implementation: namespace alias
scn::ranges
, control behavior withSCN_USE_STD_RANGES
- Move custom Ranges implementation to the public API (out from
Additions
- Add more thorough documentation, tests, benchmarks and examples
- Add
scan_list_until
Fixes and minor stuff
- Fix float parsing not being locale-agnostic when global C locale was not
"C"
(#24, thanks @petrmanek (Petr Mánek) and @amyspark for reporting) - Fix
SONAME
(#32, thanks @xvitaly (Vitaly Zaitsev)) - Use system doctest and google-benchmark if available (#28, #30, #31, thanks @xvitaly (Vitaly Zaitsev), and @leha-bot (Alex) for reporting)
- Fix CUDA compilation (#22, thanks @invexed (James Beach) for reporting)
- Move to readthedocs (https:/
/ scnlib.readthedocs.com) from https:/ / scnlib.dev - Move to GitHub Actions from Travis and Appveyor
0.3
Released 2020-02-19
Largely a bugfix release
Changes
- Remove support for partial successes
- If the reading of any of the arguments given to
scan
fail, the whole function fails read
-field removed fromresult
- If the reading of any of the arguments given to
- Overhaul list scanning
- Add
scan_list
- Add
Fixes
- Fix issues with
std::
and MSVC debug iterators (#11, #14, #18, #20)string_view - Fix some issues with scanning customized types (#15)
- Add missing support for custom-allocator
std::
s (#16)string - Fix erroneous
git
command in README (#13) - Fix README example
- Fix erroneous usage of library feature test macros
Thanks to @nanoric and @SuperWig (Daniel Marshall) for bug reports!
Removals
- Remove support for non-
std::
char_traits std::
sstring - Remove support for clang 3.6
0.2
Released 2019-10-18
Major changes
- Remove the notion of streams, and replace them with ranges
- Using a hand-written minimal ranges implementation based on NanoRange: https:/
/ github.com/ tcbrindle/ NanoRange - A lot of things changed, renamed or removed because of this
- Using a hand-written minimal ranges implementation based on NanoRange: https:/
Additions
- Add zero-copy parsing of
string_view
s from acontiguous_range
- Works like parsing a
std::
, except the pointers of thestring string_view
are directed to the input range
- Works like parsing a
- Add
scan_list
- Add experimental memory mapped file reading support
Removals
- Remove
scn::options
andscn::
overloads taking onescan - Remove parsing algorithms based on
std::strto*
,std::sto*
andstd::
from_chars - Remove reading from a
std::
basic_istream
Changes
- Rename
scan(locale, ...)
toscan_localized(...)
- Fix UB in
small_vector
usingstd::
andaligned_storage std::
aligned_union - And probably tons more that I've not written down anywhere
0.1.2
Released 2019-06-25
- Add
SCN_RANGES
CMake option - Add
scn::temp
helper function - Fix
-Wpadded
warnings on clang - Fix
-Wfloat-equal
and-Wconversion
warnings on gcc - Fix
C4146
error on UWP MSVC - Add CONTRIBUTING.md
0.1.1
Released 2019-06-25
- Add more examples
- Fix #8: Fix segfault when using
scn::cstdin()
orscn::wcstdin()
, caused by the copy and move constructor ofsmall_vector
setting data pointer tonullptr
if copying/moving from an emptysmall_vector
. (Thanks @SuperWig (Daniel Marshall) for reporting!) - Fix compilation error when using
scn::ranges::get_value
. - Fix a badge in README (thanks @p1v0t)
0.1
Released 2019-06-23
Initial release