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refactor: 💥 q_* UDL renamed to _q_*

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We had some fun exploring the STD UDLs for potential collisions,
we have learnt our lesson and know how to proceed.
Now is high time to start behaving and obeying C++ rules.
This commit is contained in:
Mateusz Pusz
2020-09-09 19:20:35 +02:00
parent 2b408f19c0
commit 9527b39005
130 changed files with 2221 additions and 2235 deletions
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docs/framework/quantities.rst
+13 -13
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@@ -48,15 +48,15 @@ values the library provides :abbr:`UDL (User Defined Literal)` s for each
be as simple as::
using namespace units::physical::si::literals;
constexpr auto d1 = 123q_km; // si::length<si::kilometre, std::int64_t>
constexpr auto d2 = 123.q_km; // si::length<si::kilometre, long double>
constexpr auto d1 = 123_q_km; // si::length<si::kilometre, std::int64_t>
constexpr auto d2 = 123._q_km; // si::length<si::kilometre, long double>
``123q_km`` should be read as a quantity of length in kilometers. Initially the
library did not use the ``q_`` prefix for UDLs but it turned out that there are
``123_q_km`` should be read as a quantity of length in kilometers. Initially the
library did not use the ``_q_`` prefix for UDLs but it turned out that there are
a few unit symbols that collide with literals already existing in C and C++
language (i.e. ``F`` (farad), ``J`` (joule), ``W`` (watt), ``K`` (kelvin),
``d`` (day), ``l`` or ``L`` (litre), ``erg``, ``ergps``). This is why the
``q_`` prefix was consistently applied to all the UDLs.
``_q_`` prefix was consistently applied to all the UDLs.
Dimension-specific Concepts
@@ -67,7 +67,7 @@ requires quantity of a concrete dimension than dimension-specific concepts can
be used::
using namespace units::physical::si::literals;
constexpr Length auto d = 123q_km; // si::length<si::kilometre, std::int64_t>
constexpr Length auto d = 123_q_km; // si::length<si::kilometre, std::int64_t>
.. note::
@@ -83,8 +83,8 @@ quantities. The usage of such a function can look as follows::
using namespace units::physical::si::literals;
using namespace units::physical::international::literals;
constexpr Speed auto v1 = avg_speed(220q_km, 2q_h);
constexpr Speed auto v2 = avg_speed(140q_mi, 2q_h);
constexpr Speed auto v1 = avg_speed(220_q_km, 2_q_h);
constexpr Speed auto v2 = avg_speed(140_q_mi, 2_q_h);
In this and all other physical units libraries such a function can be
implemented as::
@@ -142,7 +142,7 @@ but often we would like to know a specific type too. We have two options here:
- query the actual dimension, unit, and representation types::
constexpr Speed auto v = avg_speed(220q_km, 2q_h);
constexpr Speed auto v = avg_speed(220_q_km, 2_q_h);
using quantity_type = decltype(v);
using dimension_type = quantity_type::dimension;
using unit_type = quantity_type::unit;
@@ -150,7 +150,7 @@ but often we would like to know a specific type too. We have two options here:
- convert or cast to a desired quantity type::
constexpr Speed auto v1 = avg_speed(220.q_km, 2q_h);
constexpr Speed auto v1 = avg_speed(220._q_km, 2_q_h);
constexpr si::speed<si::metre_per_second> v2 = v1;
constexpr Speed auto v3 = quantity_cast<si::speed<si::metre_per_second>(v1);
@@ -166,8 +166,8 @@ Dimensionless Quantities
Whenever we divide two quantities of the same dimension we end up with a
:term:`dimensionless quantity` otherwise known as :term:`quantity of dimension one`::
static_assert(10q_km / 5q_km == 2);
static_assert(std::is_same_v<decltype(10q_km / 5q_km), quantity<dim_one, one, std::int64_t>>);
static_assert(10_q_km / 5_q_km == 2);
static_assert(std::is_same_v<decltype(10_q_km / 5_q_km), quantity<dim_one, one, std::int64_t>>);
According to the official ISO definition `dim_one` is a dimension "for which all the
exponents of the factors corresponding to the base quantities in its quantity dimension
@@ -196,7 +196,7 @@ There are two special units provided for usage with such a quantity:
For example the following code::
std::cout << quantity_cast<percent>(50.q_m / 100.q_m) << '\n';
std::cout << quantity_cast<percent>(50._q_m / 100._q_m) << '\n';
will print ``50 %`` to the console output.