Merge pull request #37 from LemLib/feat/std-format

✨ `std::format` support

.github/workflows/pros-build.yml

@@ -1,4 +1,4 @@
-name: Build Template
+name: PROS Build Template
 
 on:
   push:
@@ -16,14 +16,11 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Run LemLib/pros-build
-        id: build-template
-        uses: LemLib/[email protected]
-        with:
-          copy_readme_and_license_to_include: true
-          lib_folder_name: units
+        id: test
+        uses: LemLib/[email protected]
 
       - name: Upload Artifact
         uses: actions/upload-artifact@v4
         with:
-          name: ${{ steps.build-template.outputs.name }}
+          name: ${{ steps.test.outputs.name }}
           path: ${{ github.workspace }}/template/*

include/units/Angle.hpp

@@ -21,6 +21,13 @@ template <> struct LookupName<Quantity<std::ratio<0>, std::ratio<0>, std::ratio<
         using Named = Angle;
 };
 
+template <> struct std::formatter<Angle> : std::formatter<double> {
+        auto format(const Angle& number, std::format_context& ctx) const {
+            auto formatted_double = std::formatter<double>::format(number.internal(), ctx);
+            return std::format_to(formatted_double, "_stRad");
+        }
+};
+
 inline std::ostream& operator<<(std::ostream& os, const Angle& quantity) {
     os << quantity.internal() << " rad";
     return os;

include/units/Temperature.hpp

@@ -21,6 +21,12 @@ template <> struct LookupName<Quantity<std::ratio<0>, std::ratio<0>, std::ratio<
         using Named = Temperature;
 };
 
+template <> struct std::formatter<Temperature> : std::formatter<double> {
+        auto format(const Temperature& quantity, std::format_context& ctx) const {
+            return std::format_to(ctx.out(), "{}_k", quantity.internal());
+        }
+};
+
 inline std::ostream& operator<<(std::ostream& os, const Temperature& quantity) {
     os << quantity.internal() << " k";
     return os;

include/units/units.hpp

@@ -7,6 +7,7 @@
 #include <type_traits>
 #include <utility>
 #include <algorithm>
+#include <format>
 
 // define M_PI if not already defined
 #ifndef M_PI
@@ -183,6 +184,38 @@ template <isQuantity Q, typename quotient> using Rooted = Named<
              std::ratio_divide<typename Q::angle, quotient>, std::ratio_divide<typename Q::temperature, quotient>,
              std::ratio_divide<typename Q::luminosity, quotient>, std::ratio_divide<typename Q::moles, quotient>>>;
 
+template <isQuantity Q> struct std::formatter<Q> : std::formatter<double> {
+        auto format(const Q& quantity, std::format_context& ctx) const {
+            constinit static std::array<std::pair<intmax_t, intmax_t>, 8> dims {{
+                {Q::mass::num, Q::mass::den},
+                {Q::length::num, Q::length::den},
+                {Q::time::num, Q::time::den},
+                {Q::current::num, Q::current::den},
+                {Q::angle::num, Q::angle::den},
+                {Q::temperature::num, Q::temperature::den},
+                {Q::luminosity::num, Q::luminosity::den},
+                {Q::moles::num, Q::moles::den},
+            }};
+            std::array<const char*, 8> prefixes {"_kg", "_m", "_s", "_A", "_rad", "_K", "_cd", "_mol"};
+
+            auto out = ctx.out();
+
+            // Format the quantity value
+            out = std::formatter<double>::format(quantity.internal(), ctx);
+
+            // Add dimensions and prefixes
+            for (size_t i = 0; i != 8; i++) {
+                if (dims[i].first != 0) {
+                    out = std::format_to(out, "{}", prefixes[i]);
+                    if (dims[i].first != 1 || dims[i].second != 1) { out = std::format_to(out, "^{}", dims[i].first); }
+                    if (dims[i].second != 1) { out = std::format_to(out, "/{}", dims[i].second); }
+                }
+            }
+
+            return out;
+        }
+};
+
 inline void unit_printer_helper(std::ostream& os, double quantity,
                                 const std::array<std::pair<intmax_t, intmax_t>, 8>& dims) {
     static constinit std::array<const char*, 8> prefixes {"_kg", "_m", "_s", "_A", "_rad", "_K", "_cd", "_mol"};
@@ -313,6 +346,12 @@ template <isQuantity Q, isQuantity R> constexpr bool operator>(const Q& lhs, con
         return Name(Quantity<std::ratio<m>, std::ratio<l>, std::ratio<t>, std::ratio<i>, std::ratio<a>, std::ratio<o>, \
                              std::ratio<j>, std::ratio<n>>(static_cast<double>(value)));                               \
     }                                                                                                                  \
+    template <> struct std::formatter<Name> : std::formatter<double> {                                                 \
+            auto format(const Name& number, std::format_context& ctx) const {                                          \
+                auto formatted_double = std::formatter<double>::format(number.internal(), ctx);                        \
+                return std::format_to(formatted_double, "_" #suffix);                                                  \
+            }                                                                                                          \
+    };                                                                                                                 \
     inline std::ostream& operator<<(std::ostream& os, const Name& quantity) {                                          \
         os << quantity.internal() << " " << #suffix;                                                                   \
         return os;                                                                                                     \
@@ -355,6 +394,12 @@ constexpr Number operator""_num(unsigned long long value) {
                            std::ratio<0>, std::ratio<0>>(static_cast<double>(value)));
 }
 
+template <> struct std::formatter<Number> : std::formatter<double> {
+        auto format(const Number& number, std::format_context& ctx) const {
+            return std::formatter<double>::format(number.internal(), ctx);
+        }
+};
+
 inline std::ostream& operator<<(std::ostream& os, const Number& quantity) {
     os << quantity.internal() << " " << num;
     return os;
@@ -598,25 +643,30 @@ template <isQuantity Q, isQuantity R> constexpr Q round(const Q& lhs, const R& r
 
 // Convert an angular unit `Q` to a linear unit correctly;
 // mostly useful for velocities
-template <isQuantity Q> Quantity<typename Q::mass, typename Q::angle, typename Q::time, typename Q::current,
-                                 typename Q::length, typename Q::temperature, typename Q::luminosity, typename Q::moles>
-toLinear(Quantity<typename Q::mass, typename Q::length, typename Q::time, typename Q::current, typename Q::angle,
-                  typename Q::temperature, typename Q::luminosity, typename Q::moles>
-             angular,
-         Length diameter) {
+template <isQuantity Q>
+Quantity<typename Q::mass, typename Q::angle, typename Q::time, typename Q::current, typename Q::length,
+         typename Q::temperature, typename Q::luminosity,
+         typename Q::moles> constexpr toLinear(Quantity<typename Q::mass, typename Q::length, typename Q::time,
+                                                        typename Q::current, typename Q::angle, typename Q::temperature,
+                                                        typename Q::luminosity, typename Q::moles>
+                                                   angular,
+                                               Length diameter) {
     return unit_cast<Quantity<typename Q::mass, typename Q::angle, typename Q::time, typename Q::current,
                               typename Q::length, typename Q::temperature, typename Q::luminosity, typename Q::moles>>(
         angular * (diameter / 2.0));
 }
 
 // Convert an linear unit `Q` to a angular unit correctly;
 // mostly useful for velocities
-template <isQuantity Q> Quantity<typename Q::mass, typename Q::angle, typename Q::time, typename Q::current,
-                                 typename Q::length, typename Q::temperature, typename Q::luminosity, typename Q::moles>
-toAngular(Quantity<typename Q::mass, typename Q::length, typename Q::time, typename Q::current, typename Q::angle,
-                   typename Q::temperature, typename Q::luminosity, typename Q::moles>
-              linear,
-          Length diameter) {
+template <isQuantity Q>
+Quantity<typename Q::mass, typename Q::angle, typename Q::time, typename Q::current, typename Q::length,
+         typename Q::temperature, typename Q::luminosity,
+         typename Q::moles> constexpr toAngular(Quantity<typename Q::mass, typename Q::length, typename Q::time,
+                                                         typename Q::current, typename Q::angle,
+                                                         typename Q::temperature, typename Q::luminosity,
+                                                         typename Q::moles>
+                                                    linear,
+                                                Length diameter) {
     return unit_cast<Quantity<typename Q::mass, typename Q::angle, typename Q::time, typename Q::current,
                               typename Q::length, typename Q::temperature, typename Q::luminosity, typename Q::moles>>(
         linear / (diameter / 2.0));

src/main.cpp

@@ -6,13 +6,18 @@
 
 constexpr int r2i(double value) { return static_cast<int>(value >= 0.0 ? value + 0.5 : value - 0.5); }
 
-/**
- * Runs initialization code. This occurs as soon as the program is started.
- *
- * All other competition modes are blocked by initialize; it is recommended
- * to keep execution time for this mode under a few seconds.
- */
 void initialize() {
+    std::cout << std::format("{:.2f}", 15.2_cm) << std::endl; // should output 0.15_m
+    std::cout << std::format("{:.2f}", 180_stDeg) << std::endl; // should output 3.14_stRad
+    std::cout << std::format("{:.2f}", 0_celsius) << std::endl; // should output 273.15
+    std::cout << std::format("{:.2f}", 1.2345) << std::endl;
+    std::cout << units::pow<5>(505_cm) * 15_celsius << std::endl;
+    std::cout << std::format("{:.2f}", units::pow<5>(505_cm) * 15_celsius) << std::endl;
+    Number a(2.123);
+    std::cout << std::format("{:.2f}", a) << std::endl;
+}
+
+constexpr void miscTests() {
     units::AccelerationPose a(1_mps2, 2_mps2);
     Number num = Number(1.0);
     num = Number(0.0);
@@ -30,12 +35,18 @@ void initialize() {
                                          std::ratio<0>, std::ratio<0>, std::ratio<0>>(5.0));
     units::max(10_celsius, Quantity<std::ratio<0>, std::ratio<0>, std::ratio<0>, std::ratio<0>, std::ratio<0>,
                                     std::ratio<1>, std::ratio<0>, std::ratio<0>>(1.0));
+}
+
+constexpr void v3dTests() {
     // check Vector3D overloads
     units::Vector3D<Length> v3a = 2 * units::V3Position(2_in, 2_in, 2_in) * 2;
     units::Vector3D<Length> v3b = units::V3Position(2_in, 2_in, 2_in) / 2.0;
     units::Vector3D<Area> v3c = 2_in * units::V3Position(2_in, 2_in, 2_in);
     units::Vector3D<Area> v3d = units::V3Position(2_in, 2_in, 2_in) * 2_in;
     units::Vector3D<Number> v3e = units::V3Position(2_in, 2_in, 2_in) / 2_in;
+}
+
+constexpr void v2dTests() {
     // check Vector2D overloads
     units::Vector2D<Length> v2a = units::V2Position(2_in, 2_in) / 2;
     units::Vector2D<Length> v2b = 2 * units::V2Position(2_in, 2_in) * 2;
@@ -81,12 +92,14 @@ constexpr double doubleAssignmentTests() {
     return d;
 }
 
-void numberOperatorTests() {
+constexpr void numberOperatorTests() {
     using namespace units_double_ops;
     static_assert(1_num + 2 == 3);
     static_assert(1 + 2_num <= 3);
     static_assert(1 / 2_num >= 0);
 
     static_assert(numAssignmentTests() == 0);
     static_assert(doubleAssignmentTests() == 1);
-}
+}
+
+constexpr void formatTests() {}