Release Notes¶

mp-units¶

2.4.0 November 5, 2024¶

(!) feat: phase_velocity and group_velocity aliases removed from ISQ by ISO
feat: iec::bit using-declared in iec::unit_symbols
feat: common unit symbols now use EQUIV{u1, u2, ...} syntax
feat: scaled_unit symbol printing improved ([] around the entire unit, small magnitude values do not use a power of 10 anymore)
feat: scaled_unit does not have a priority over derived_unit anymore
feat: fractional exponents support added to mag_power
feat: tag types are now required to be empty
feat: magnitude text now obeys formatting parameters and knows how to print constants
feat: added support for printing powers of magnitude constants
feat: SymbolicConstant concept added
feat: common_unit selection algorithm improved to make rev + rad return rad
feat: litre text symbol changed from l to L to avoid ambiguity with 1
feat: alternative litre unit symbol L added to prevent ambiguities with 1
feat: Unicode unit symbols
feat: π added as an alias for pi
feat: expr_pow extended to remove redundancy in callers
feat: DerivedDimensionExpr, DerivedQuantitySpecExpr and DerivedUnitExpr removed
feat: MagnitudeSpecExpr and PowerVBase removed and some functions renamed to limit possible ambiguity in overload resolution
feat: std::is_object constraint applied to value_type_t
feat: quantity_values are now defined on top of std::chrono::duration_values
feat: from now on truncation is not allowed in compound assignment
feat(example): currency example now uses chrono::time_point and has better interfaces
feat(example): treat_as_floating_point specializations for examples' types removed
(!) refactor: all iec quantity specifications are now deprecated and moved to isq
(!) refactor: mag_constant now takes a symbol and a value and the class deriving from it must be final
(!) refactor: op==(U1, U2) now checks for the same type (old behavior available as equivalent(U1, U2)) + convertible now verifies associated quantity_spec as well
(!) refactor: ascii -> portable, unicode -> utf8, 'A' -> 'P'
(!) refactor: char_traits removed from fixed_string
(!) refactor: convertibility traits and concepts refactored to use bool flags instead of wrappers
(!) refactor: tag types should not expose their members
refactor: convertible(U1, U2) implementation simplified
refactor: abs moved to constexpr_math.h
refactor: unit_symbol_impl simplified
refactor: unit_symbol_formatting moved to a dedicated header file
refactor: shorten_T removed
refactor: magnitude interface cleanup
refactor: derived_from_the_same_base_dimension no longer needed
refactor: one_of usage removed from the fixed_string deduction guides
refactor: quantity.h is not needed in constants.h (unit.h is enough)
refactor: SameDimension concept is not needed and can be inlined in DimensionOf
refactor: framework Unicode symbols are now spelled using their codes
refactor: QuantitySpecWithNoSpecifiers removed and kind_of definition simplified
refactor: treat_as_floating_point simplified and extended to use std::chrono::treat_as_floating_point_v
refactor: wrapped_type_t reuses std::indirectly_readable_traits
refactor: expr_fractions takes direct OneType type now instead of a trait
refactor: Unicode symbols description reworked based on the latest SG16 recommendations
refactor: Mutable concept applied to quantity and quantity_point
refactor: explicit cleanup for deduction guides of quantity and quantity_point
refactor: point_origin_interface::op- cleanup
refactor: QuantityLikeImpl refactored to conform to API Reference by @JohelEGP
refactor: get_complexity refactored to be 0-based and not account for a number of arguments in a list
refactor: get_complexity refactored to returned maximum complexity of an element (instead of the sum of elements)
refactor(test): derived_quantity refactored to child_quantity
fix: missing are_ingredients_convertible overloads added
fix: constraints for magnitude added for scaled_unit and fixed common_unit instantiating it incorrectly
fix: according to ISO 80000-16 % should always be prefixed with space
fix: extraneous space in unit symbol having only denominators removed
fix: explicit cast added to less for magnitudes to fix clang-arm64 conversion error
fix: common_unit handling fixed for some corner cases
fix: math functions constraints fixed
fix: operator*(M, U u) fixed for U being scaled_unit
fix: subsumption of QuantityKindSpec fixed
fix: ValuePreservingTo fixed to apply std::remove_cvref_t on FromRep
fix: compound assignment operations on quantities now behave the same as on the underlying representation types
fix: QuantityConvertibleTo used in quantity_point compound assignment
fix: convertible_kinds implementation fixed
fix(tests): freestanding build fixed
test: unit tests for the inverse of mag_constant added
test: Unicode symbols used in unit tests
test: more std::chrono tests added
test: commutativity tests added to ISQ
test: one kind_of test added to reference tests
test: pow<0> and pow<1> tests added for dimensions
test: more get_common_quantity_spec tests added
build: setting of some test_package CMake options enabled only for a cxx_modules build
ci: sudo apt update added for documentation.yml in hope that it will resolve missing system packages issue
ci: MSVC added to the CI
ci: the latest not-released docs will use "HEAD" as a version from now on
ci: documentation action should run on a new tag as well
ci: documentation action limited only to commits that change documentation files
ci: non-documentation actions should not run on tags
docs: missing systems added to the "Project Structure" chapter
docs: graphs of ISQ kind hierarchies improved
docs: category of the ISO meeting reports changed to "WG21 Updates"
docs: blog comments support added
docs: Part 1-5 articles of the ISQ series added
docs: "Symbols of scaled units" chapter added + minor updates to scaled and common units chapters
docs: conan profile updated to present gcc-14 instead of gcc-12 which is no longer supported
docs: "Why derived units order is not preserved from the multiplication?" chapter added to FAQ
docs: "Many shades of the same unit" extended with a note about the derived units order
docs: API Reference now presents index.html instead of full.hml

2.3.0 September 27, 2024¶

(!) feat: delta and absolute construction helpers
(!) feat: Conan and CMake options changed as requested at ConanCenter code review
(!) feat: unit_can_be_prefixed removed - from now on all named units can be prefixed
feat: formatting functions for units and dimensions marked as constexpr to enable compile-time text formatting
feat: qp1.quantity_from(qp2) added
feat: non-member swap added for fixed_string
feat: simplified inplace_vector added
feat: text output for angular units improved (space before symbol removed)
feat: representation type template parameter added to value conversion functions
feat: all tags in the expression templates are now ordered by the type names
feat: convertibility of a quantity with a unit one with the raw value added
feat: import std; support added
feat: compute values for rational magnitude powers (thanks @chiphogg)
feat: value_cast<Representation, Unit>() complementary conversion function added
feat: hw_voltage example added
feat: MP_UNITS_IMPORT_STD and MP_UNITS_MODULES handled properly in test_package.cpp
feat: complex quantity character added
feat: iec::var unit added
feat: type_list_unique added
feat: for_each on std::tuple added
feat: common_unit support added
(!) refactor: quantity_point_like_traits now use numerical value instead of the quantity
(!) refactor: iec80000 system renamed to iec
(!) refactor: mag_pi is now mag<pi>
(!) refactor: common_XXX() functions renamed to get_common_XXX()
refactor: error messages-related improvements
refactor: [[nodiscard]] and consteval set for some magnitude-related functions
refactor: degree Celsius and Fahrenheit symbols text now use Unicode codepoints
refactor: dimension_symbol and units_symbol refactored to use inplace_vector
refactor: unit_symbol and dimension_symbol refactored for readability and consteval
refactor: binary operators of quantity and quantity_point are now hidden friends
refactor: tag types-related operators are now hidden friends as well
refactor: ValuePreservingTo concept added
refactor: perfect forwarding interfaces improved
refactor: Representation concepts now requires WeaklyRegular instead of std::regular
refactor: quantity_point default-constructibility removed from the quantity_from constraints
refactor: has_common_type_v simplified
refactor: is_power_of_quantity_spec and is_power_of_dim variable templates converted to concepts
refactor: unnecessary custom versions of is_specialization_of removed
refactor: is_derived_from_specialization_of_v added and applied to remove custom traits
fix: signatures of capacity functions of fixed_string fixed
fix: MP_UNITS_API_NO_CRTP handling fixed
fix: MP_UNITS_HOSTED branch added to core.h
fix: mkdocs dependencies fixed in the gitpod dockerfile
fix: MP_UNITS_API_CONTRACTS should have a priority over headers availability
fix: si.h and angular.h now properly include hacks.h to define MP_UNITS_HOSTED before its usage
fix: quantity scaling between different prefixes improved
fix: conversion operator to std::chrono types fixed
fix: std::format does not always use Char* as iterators
fix: complex_power & co fixed
fix: __cpp_deleted_function workaround for clang-19 added
test: conversion to chrono unit tests added
test: unit tests for creating a quantity from a volatile variable
test: increase tolerance for certain math tests to two epsilon by @burnpanck
test: std::complex-based quantities tests added
build: conanfile bumped to use catch2/3.7.0
build: conanfile bumped to use fmt/11.0.1
build: minimum required CMake version bumped to 3.25
build: duplicated cmake_minimum_required commands removed
build: minimum conan version set to 2.0.15
build: MSVC compilation enabled for the library part by @czjhoppe
build: Dockerfile updated for gitpod
build: generate() in test_package now correctly propagates project's options
build: target_include_directories is not needed anymore
build: target_compile_features now uses CMAKE_CXX_STANDARD
build: package_type is dynamically set in conanfile.py depending if we build modules or not
build(conan): packaging improved
ci: added test for upstream clang on macos-14, as an example for an arm64 platform by @burnpanck
style: pre-commit updated to clang-format-18.1.8
docs: "Strong Angular System" chapter added
docs: docs updated to use new spelling for Conan options
docs: "Interface Introduction" chapter updated
docs: St. Louis 2024 report added
docs: "Radians and degrees support" added
docs: Rework of "Getting Started" section
docs: "API Reference" support added (thanks @JohelEGP)
docs: "Generating API reference" chapter added
docs: minor formatting and spelling improvements to the "CONTRIBUTING.md"
docs: "Unit symbols" chapter added
docs: examples line numbers fixed
docs: "Text Formatting" tag removed from avg_speed example
docs: line breaks in mermaid graphs fixed
docs: 2.3.0 release added

2.2.1 July 3, 2024¶

(!) feat: Conan and CMake options refactored

2.2.0 June 14, 2024¶

(!) feat: C++ modules support added by @JohelEGP
(!) feat: New formatting specification implemented
(!) feat: has_unit_symbol support removed
(!) feat: ABI concerns resolved with introduction of u8 strings for symbols
(!) feat: API-related Conan, CMake, and preprocessor options redesigned
(!) feat: core.h removed
(!) feat: from now on units, dimensions, quantity specifications, and point origins have to be marked as final
feat: implicit point origins support added
feat: unit default point origin support added
feat: fma, isfinite, isinf, and isnan math function added by @NAThompson
feat: fma for quantity points added
feat: quantity_point support added for quantity_cast and value_cast
feat: value_cast<Unit, Representation> added
feat: value_cast<Quantity>(q), value_cast<Quantity>(qp) and value_cast<QuantityPoint>(qp) added by @burnpanck
feat: interconvertible(QuantitySpec, QuantitySpec) added
feat: qp.quantity_from_zero() added
feat: value_type type trait added
feat: do not print space between a number and percent or per_mille
feat: ppm parts per million added by @nebkat
feat: atan2 2-argument arctangent added by @nebkat
feat: fmod floating-point division remainder added by @nebkat
feat: remainder IEEE division remainder added by @nebkat
feat: std::format support added
feat: unit text output support added
feat: formatting error messages improved
feat: improve types readability by eliminating extraneous () in references, prefixes, and kind_of
feat: dimension and unit text output added
feat: some light and radiation ISQ quantities added
feat: allow configuring GSL library use
feat: freestanding support added
(!) refactor: zero_Fahrenheit renamed to zeroth_degree_Fahrenheit
(!) refactor: SI-related trigonometric functions moved to the si subnamespace
(!) refactor: math.h header file broke up to smaller pieces
(!) refactor: fixed_string interface refactored
(!) refactor: ReferenceOf does not take a dimension anymore
(!) refactor: 'o' replaced with '1' as a modifier for unit_symbol_solidus::one_denominator
(!) refactor: get_kind() now returns kind_of
(!) refactor: FMT macros moved to compat_macros.h
(!) refactor: fixed_string refactored to reflect the latest changes to P3094R2
(!) refactor: basic_symbol_text renamed to symbol_text
(!) refactor: ratio hidden as an implementation detail behind mag_ratio
(!) refactor: framework.h introduced
(!) refactor: type list tools made an implementation detail of the library
(!) refactor: header files with the entire system definitions moved up in the directory tree
(!) refactor: absolute_point_origin does not use CRTP anymore
refactor: system's units do not inherit from one another anymore
refactor: all units made final
refactor: math functions constraints refactored
refactor: si_quantities.h added to improve compile-times
refactor: validate_ascii_string refactored to is_basic_literal_character_set
refactor: underlying_type split to wrapped_type and value_type and used in code
refactor: code refactored to comply with clang-tidy
refactor: remove dependency on <ranges> header and switch to use an iterator-based copy algorithm
refactor: terminate replaced with abort and a header file added
refactor: most std::remove_const_t removed and some replaced with the GCC-specific workaround
refactor: not needed remove_reference_t and remove_cvref_t removed
refactor: binary operators of quantity and quantity_point are now hidden friends
fix: QuantityLike conversions required Q::rep instead of using one provided by quantity_like_traits
fix: QuantitySpec[Unit] replaced with make_reference in value_cast
fix: ice_point is now defined with the integral offset from absolute_zero
fix: performance regression in sudo_cast fixed
fix: explicit object parameter support fixed
fix: missing version header file added to hacks.h
fix: quantity_cast to accept lvalue references (thanks @burnpanck)
fix: value_cast with lvalue references to quantity_point (thanks @burnpanck)
docs: project blog and first posts added
docs: project documentation layout refactored
docs: "Interoperability with Other Libraries" chapter added
docs: "Framework Basics" chapters updated and cleaned up
docs: smoot unit example added to the main page
docs: "Code Example" chapter renamed to "Look and Feel" and reordered in TOC to be after "Quick Start"
docs: "Quick Start" chapter reworked to be simpler and include quantity points
docs: "Quantity points" chapter extended
docs: "The Affine Space" chapter updated to reflect the recent design changes
docs: "Working with Legacy interfaces" chapter added
docs: "Text Output" chapter updated
docs: mkdocs social plugin enabled
docs: project logo and custom color scheme added
docs: minimum compiler requirements updated
docs: unit symbols admonition extended in the "Quick Start" chapter
docs: Cairo dependency described in the MkDocs section
docs: "hello units" example updated with dimensions output
docs: "Text Output" chapter updated with the recent formatting changes
docs: formatting grammar language changed to EBNF
docs: "Project structure" chapter expanded
docs: CITATION.cff updated
(!) build: Conan and CMake options refactored
(!) build: MP_UNITS_AS_SYSTEM_HEADERS renamed to MP_UNITS_BUILD_AS_SYSTEM_HEADERS
(!) build: MP_UNITS_BUILD_LA and MP_UNITS_IWYU CMake options now have _DEV_ in the name
build: gsl-lite updated to 0.41.0
build: catch2 updated to 3.5.1
build: fmt updated to 10.2.1
build: gitpod environment updated
build: check_cxx_feature_supported added
build: IWYU path handling fixed
build: IWYU enabled on GCC
build: CMAKE_EXPORT_COMPILE_COMMANDS flag enabled for the developer's build
build(conan): generate() now set cache_variables
build(conan): can_run check added before running tests
ci: Conan and CMake CI now use different cache names
ci: gcc-14 added
ci: clang-tidy CI added

2.1.1 May 16, 2024¶

fix: unit tests compilation on gcc-14 fixed
fix: explicit this parameter support fixed

2.1.0 December 9, 2023¶

(!) feat: inverse() support added for dimensions, quantity_spec, units, and references (1 / s will now create quantity and not a Unit)
(!) feat: quantity_point does not provide zero() anymore
(!) feat: quantity_spec and its kind should not compare equal
(!) feat: mutating interface removed from fixed_string
(!) feat: common_type with a raw value is not needed anymore as for a long time now raw values are not convertible to the dimensionless quantities
(!) feat: symbol_text definition simplified
(!) feat: users are now allowed to inherit their own types from absolute point origins
(!) feat: interoperability with other libraries redesigned
feat: basic_fixed_string(const CharT*, std::integral_constant<std::size_t, N>) constructor added
feat: isq::activity added and becquerel definition updated to benefit from it
feat: gray and sievert now have correct associated quantity kinds
feat: UnitCompatibleWith concept added and applied to in(U) and force_in(U) functions
feat: quantities can now be multiplied and divided by units (no parenthesis needed anymore)
feat: Magnitude / Unit operator added
feat: equality for dimensions now will allow derived classes as well (but not from derived_dimension)
feat: zero_Fahrenheit point origin added
feat: equivalent point origins handling improved
feat(example): unit symbols added to the currency example
(!) refactor: unit_symbol<fmt>(U) signature refactored and the resulting text can now also be used at runtime
(!) refactor: make_xxx factory functions replaced with two-parameter constructors
(!) refactor: unit_symbol changed to consteval
refactor: in(U) and force_in(U) now return auto to provide better diagnostics on clang
refactor: quantity operators constraints refactored
refactor: more type members added to fixed_string definition
refactor: unit_symbol_formatting enums now use std::int8_t as a representation type
fix: symbols of named dimensionless units with the ratio = 1 were not printed
fix: iterator is now properly updated for all cases in unit_symbol
fix: Fahrenheit conversion ratio was inverted
fix: CommonlyInvocableQuantities was overconstrained for the current library design
fix: are_ingredients_convertible now mandates explicit conversion for To dimensionless quantities
fix: quantity_point::point_for(PO) constraints fixed
fix(example): latitude and longitude fixed to include 0 for N and E respectively
ci: clang-17 enabled
ci: apple-clang-15 enabled
ci: Added C++23 builds to the CI matrix
docs: "Getting Started" chapters updated
docs: "Basic Concepts" and "Interface Introduction" chapters updated
docs: "Design Overview" chapter added and "Concepts" chapter reworked
docs: "Output stream formatting" chapter updated
docs: "Default formatting" chapter updated
docs: "Derived unit symbols generation" chapter added
docs: outdated affine space chapter updated
docs: CameCase concept identifiers FAQ added
docs: gravitational_potential_energy equation fixed on a graph
docs: YouTube video link updated to the C++ on Sea 2023
docs: ISO papers reference added to docs and README
docs: a representation type in a dimensionless quantity FAQ fixed
docs: titles added to some important admonitions
docs: "Terms and Definitions" slightly updated
docs: "canonical unit" added to glossary and its documentation in code was updated
docs: Design overview graph updated

2.0.0 September 24, 2023¶

units namespace renamed to mp_units (#317)
header files in the <mp-units/...> rather then in <units/...> (#317)
the downcasting facility is removed (#383, #211, #32)
unified and simplified quantity creation (#274)
determining the best way to create a quantity (#413)
V2 quantity_point (#414)
introduction of quantity_spec to store not only dimension but also additional information about quantities (#405)
quantity now takes reference object, which aggregates quantity_spec and a unit and a representation type
units, prefixes, dimensions, quantity specifications, and references are passed as NTTPs to templates and provide arithmetic operations and comparison
expression templates consistently used in all derived types to increase the readability (#351, #166)
derived dimensions are now factors of only base dimensions (#281)
convertibility of derived quantities (#427)
dimensions, quantity specifications, units, and references are now composable, significantly reducing the number of definitions and resulting types
heavily simplified unit systems definitions (no need to define unnamed derived units, systems-specific dimensions, aliases for quantities, concepts, UDLs, ... anymore)
improved definition of all systems
support for ISO 80000 Part 3-6 quantities
faster than lightspeed constants (#169)
extensions to quantity formatting with fmt
quantity_kind removed
improved casting of unit with .in(Unit), .force_in(Unit) for quantity and quantity_spec
numerical value accessor safety improved with .numerical_value_in(Unit) and .force_numerical_value_in(Unit)
quantity can no longer be constructed with a raw value (#434)
Implicit construction of quantities from a value (#410)
quantity_point can no longer be constructed with just a quantity and an explicit PointOrigin is always needed
ceil and floor are dangerous (#432)
quecto, ronto, ronna, quetta new SI prefixes support
comparison against zero added (#487)
documentation rewritten from scratch
many smaller changes not possible to address with the previous design (#205, #210, #134)

0.8.0 June 14, 2023¶

(!) refactor: common_quantity, common_quantity_for, common_quantity_point, common_quantity_kind, and common_quantity_point_kind removed
(!) refactor: named_derived_unit removed as it was not used
(!) refactor: derived_unit renamed to derived_scaled_unit
(!) refactor: unit renamed to derived_unit
(!) refactor: U::is_named removed from the unit types and replaced with NamedUnit concept
(!) refactor: PrefixFamily support removed
(!) refactor: mi(naut) renamed to nmi
(!) refactor: knot unit helper renamed to kn in FPS
(!) refactor: knot text symbol changed from "knot" to "kn"
refactor: quantity op+() and op-() reimplemented in terms of reference rather then quantity types
refactor(example): glide_computer now use dimensionless quantities with ranged_representation as rep
feat: HEP system support added (thanks @RalphSteinhagen)
feat: floor(), ceil(), and round() support added (thanks @hofbi)
feat: std::format support for compliant compilers added
feat: conversion helpers from mp-units to std::chrono types added
feat: math functions can now be safely used with user-defined types
feat: conversion from quantity_point to std::chrono::time_point added
feat: nautical_mile_per_hour and knot added to si::international system
(!) fix: add quantity_point::origin, like std::chrono::time_point::clock
fix: enable any prefixes for most of the named units (beside those that use prefixes already)
fix: hectare definition fixed to be a prefixed version of are + other units
fix: account for different dimensions in quantity_point_cast's constraint
fix: output stream operator now properly handles state
fix: fmt algorithms were overconstrained with forward_iterator
fix: CTAD for aliases fixed
fix: derived_ratio calculation
fix: fill_t assignment operator fixed
fix: improve downcast mode off
fix: radioactivity header compilation fixed
fix: si::hep::dim_momentum duplicated definition fixed
fix: fps can now coexist with international system
fix: public headers fixed to be standalone
test: standalone public headers tests added
(!) build: CMake generator in Conan is no longer obtained from an environment variable
(!) build: Required Conan version bumped to 1.48
(!) build: Conan 1.48 does not set CMAKE_BUILD_TYPE in the conan_toolchain.cmake anymore
build: AppleClang 13 support added (thanks @fdischner)
build: most of the conanfile.py refactored to be Conan 2.0 ready
build: validate() replaced with configure() to raise errors during conan install in Conan 1.X
build: minimum Conan version changed to 1.40
build: linear-algebra Conan repo is no needed anymore
build: Gitpod support added
build: clang-format-15 support added
build: export config to local build (#322)
build: fix export name of mp-units-system
build: fmt updated to 8.0.1
build: gsl-lite updated to 0.40.0
build: catch2 updated to 2.13.9
build: doxygen updated to 1.9.4
build: linear_algebra/0.7.0 switched to wg21-linear_algebra/0.7.2
ci: VS2022, gcc-11, clang-13, clang-14, and AppleClang 13 support added
ci: pre-commit support added (thanks @hofbi)
docs: Project documentation updated
docs: CITATION.cff file added
docs: CONTRIBUTING.md updated

0.7.0 May 11, 2021¶

(!) refactor: ScalableNumber renamed to Representation
(!) refactor: output stream operators moved to the units/quantity_io.h header file
(!) refactor: Refactored the library file tree
(!) refactor: quantity::count() renamed to quantity::number()
(!) refactor: data system renamed to isq::iec80000 (quantity names renamed too)
(!) refactor: *deduced_unit renamed to *derived_unit
(!) refactor: got rid of a noble_derived_unit
refactor: quantity (kind) point updated to reflect latest changes to quantity
refactor: basic concepts, quantity and quantity_cast refactored
refactor: abs() definition refactored to be more explicit about the return type
feat: quantity (point) kind support added (thanks @johelegp)
feat: quantity references support added (thanks @johelegp)
feat: quantity aliases support addded
feat: interoperability with std::chrono::duration and other units libraries
feat: CTAD for dimensionless quantity added
feat: modulation_rate support added (thanks @go2sh)
feat: SI prefixes for isq::iec80000 support added (thanks @go2sh)
feat: a possibility to disable quantity UDLs support with UNITS_NO_LITERALS preprocessor define
feat: a support to define ISQ derived dimensions in terms of different number or order of components
perf: preconditions check do not influence the runtime performance of a Release build
perf: quantity_cast() generates less assembly instructions
perf: temporary string creation removed from quantity::op<<()
perf: value initialization for quantity value removed (left with a default initialization)
perf: limited the equivalent trait usage
perf: limited the C++ Standard Library headers usage
perf: rvalue references support added for constructors and getters
(!) fix: exp() has sense only for dimensionless quantities
(!) fix: dim_torque now properly divides by an angle (instead of multiply) + default unit name change
fix: quantity's operators fixed to behave like the underlying types do
fix: quantity_cast() fixed to work correctly with representation types not convertible from std::intmax_t
fix: ambiguous case for empty type list resolved
fix: downcasting facility for non-default-constructible types
fix: restore user-warnings within the library implementation
fix: the text symbol of foot_pound_force and foot_pound_force_per_second
fix: quantity modulo arithmetics fixed
(!) build: Conan testing version is now hosted on Artifactory
(!) build: Linear Algebra is now hosted on its Artifactory
(!) build: BUILD_DOCS CMake option renamed to UNITS_BUILD_DOCS
build: doxygen updated to 1.8.20
build: catch2 updated to 2.13.4
build: fmt updated to 7.1.3
build: ms-gsl replaced with gsl-lite/0.38.0
build: Conan generator switched to cmake_find_package_multi
build: Conan CMakeToolchain support added
build: CMake scripts cleanup
build: ccache support added
ci: CI switched from Travis CI to GitHub Actions

0.6.0 September 13, 2020¶

feat: quantity_point support added (thanks @johelegp)
feat: Added angle as SI base dimension (thanks @kwikius)
feat: si::angular_velocity support added (thanks @mikeford3)
feat: FPS system added (thanks @mikeford3)
feat: Added support for mathematical function exp(quantity)
feat: Localization support for text output added (thanks @rbrugo)
feat: Added STL random number distribution wrappers (thanks @yasamoka)
(!) refactor: Refactored and cleaned up the library file tree
(!) refactor: q_* UDL renamed to _q_*
(!) refactor: UDLs with "per" in name renamed from *p* to *_per_*
(!) refactor: ratio changed to the NTTP kind
(!) refactor: exp and Exp renamed to exponent and Exponent
(!) refactor: Scalar concept renamed to ScalableNumber
(!) refactor: Dimensionless quantities redesigned to be of a quantity type
refactor: math.h function signatures refactored to use a Quantity concept (thanks @kwikius)
refactor: [[nodiscard]] added to many functions
fix: si::day unit symbol fixed to d (thanks @komputerwiz)
fix: si::mole unit symbol fixed to mol (thanks @mikeford3)
(!) build: gcc-9 is no longer supported (at least gcc-10 is required)
build: Visual Studio 16.7 support added
build: linear_algebra updated to 0.7.0/stable
build: fmt updated to 7.0.3
build: range-v3 updated to 0.11.0
build: catch2 updated to 2.13.0
build: doxygen updated to 1.8.18
build: ms-gsl 3.1.0 dependency added
build: Removed the dependency on a git submodule with common CMake scripts

0.5.0 May 17, 2020¶

Major refactoring and rewrite of the library
Units are now independent from dimensions
Dimensions now depend on units (base or coherent units are provided in a class template)
Quantity gets a Dimension template parameter again (as unit does not provide information about its dimension anymore)
Spaceship operator support added
Added official CGS system support
Added official data information system support
Repository file tree cleanup
ratio refactored to contain Exp template parameter (thanks a lot @oschonrock!)
SI fundamental constants added
q_ prefix applied to all the UDLs (thanks @kwikius)
unknown_unit renamed to unknown_coherent_unit
Project documentation greatly extended and switched to Sphinx
A few more usage examples added
ASCII-only output support added (thanks @yasamoka)
Representation values formatting extended (thanks @rbrugo)
Output streams formatting support added
Linear algebra from std::experimental::math support added
Named SI units and their dimensions added (thanks @rbrugo
libfmt updated to 6.2.0
Added absolute functions and epsilon to math.h (thanks @mikeford3)
Added a lot of prefixes to named units and introduced alias_unit (thanks @yasamoka)
Linking with Conan targets only when they exists (#98)
All physical dimensions and units put into physical namespace
CMake improvements
Velocity renamed to speed

Many thanks to GitHub users @oschonrock, @kwikius, and @i-ky for their support in drafting a new library design.

0.4.0 Nov 17, 2019¶

Support for derived dimensions in exp added
Added pow() and sqrt() operations on quantities
units removed from a std::experimental namespace
Downcasting facility refactored so the user does not have to write the boilerplate code anymore
From now on base dimensions should inherit from base_dimension class template
Added unit symbols definitions to base_dimension and derived units
Added support for operator<< on quantity
fmt support added
Derived unit factory helpers refactored
Refactored the way prefixed units are defined

0.3.1 Sep 18, 2019¶

cmcstl2 dependency changed to range-v3 0.9.1

0.3.0 Sep 16, 2019¶

The design as described on CppCon 2019 talk (https://youtu.be/0YW6yxkdhlU)
Applied the feedback from the Cologne evening session
upcasting_traits renamed to downcasting_traits
Dimension template parameter removed from quantity
units moved to a std::experimental namespace
Leading underscore prefix removed from UDLs
Added a few more derived dimensions
meter renamed to metre
Missing operator* added
Predefined dimensions moved to a dedicated directory
dimension_ prefix removed from names of derived dimensions
cmcstl2 library updated to 2019.09.19
base_dimension is a value provided as const& to the exp type
integrated with Compiler Explorer
gsl-lite dependency removed
Fractional dimension exponents support added
QuantityOf concept introduced
quantity_cast<U, Rep>() support added

0.2.0 July 18, 2019¶

The design as described on C++Now 2019 talk (https://youtu.be/wKchCktZPHU)
Added C++20 features supported by gcc-9.1 (std::remove_cvref_t, down with typename, std::type_identity)
Compile-time performance optimizations (type_list, common_ratio, ratio, conditional_t)

0.1.0 May 18, 2019¶

Initial library release
Begin semantic versioning
The last version to work with gcc-8