Math: make all literals usable with Utility::Tweakable.

doc/changelog.dox

@@ -38,6 +38,14 @@ See also:
 
 @section changelog-latest Changes since 2018.10
 
+@subsection changelog-latest-new New features
+
+@subsubsection changelog-latest-new-math Math library
+
+-   Support for using the @ref Math::Deg, @ref Math::Rad, @ref Math::Half,
+    @ref Math::Color3 and @ref Math::Color4 literals with the new experimental
+    @ref Corrade::Utility::Tweakable utility. See also @ref tweakableliterals.
+
 @subsection changelog-latest-bugfixes Bug fixes
 
 -   Fixed @ref Platform::Sdl2Application and @ref Platform::GlfwApplication to

src/Magnum/CMakeLists.txt

@@ -132,6 +132,7 @@ endif()
 
 # Files shared between main library and math unit test library
 set(MagnumMath_SRCS
+    Math/Angle.cpp
     Math/Color.cpp
     Math/Half.cpp
     Math/Functions.cpp

src/Magnum/Math/Angle.cpp

@@ -0,0 +1,125 @@
+/*
+    This file is part of Magnum.
+
+    Copyright © 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018
+              Vladimír Vondruš <mosra@centrum.cz>
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the "Software"),
+    to deal in the Software without restriction, including without limitation
+    the rights to use, copy, modify, merge, publish, distribute, sublicense,
+    and/or sell copies of the Software, and to permit persons to whom the
+    Software is furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included
+    in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+    THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+    FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+    DEALINGS IN THE SOFTWARE.
+*/
+
+#include "Angle.h"
+
+#if defined(DOXYGEN_GENERATING_OUTPUT) || defined(CORRADE_TARGET_UNIX) || (defined(CORRADE_TARGET_WINDOWS) && !defined(CORRADE_TARGET_WINDOWS_RT)) || defined(CORRADE_TARGET_EMSCRIPTEN)
+#include <algorithm>
+#include <Corrade/Containers/ArrayView.h>
+#include <Corrade/Utility/String.h>
+#include <Corrade/Utility/TweakableParser.h>
+
+namespace Corrade { namespace Utility {
+
+std::pair<TweakableState, Magnum::Math::Deg<Magnum::Float>> TweakableParser<Magnum::Math::Deg<Magnum::Float>>::parse(const Containers::ArrayView<const char> value) {
+    char* end;
+    const Magnum::Float result = std::strtof(value, &end);
+
+    if(end == value.begin() || std::find(value.begin(), value.end(), '.') == value.end()) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(!String::viewEndsWith(value, "_degf")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _degf";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(end != value.end() - 5) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    return {TweakableState::Success, Magnum::Math::Deg<Magnum::Float>{result}};
+}
+
+std::pair<TweakableState, Magnum::Math::Deg<Magnum::Double>> TweakableParser<Magnum::Math::Deg<Magnum::Double>>::parse(const Containers::ArrayView<const char> value) {
+    char* end;
+    const Magnum::Double result = std::strtod(value, &end);
+
+    if(end == value.begin() || std::find(value.begin(), value.end(), '.') == value.end()) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(!String::viewEndsWith(value, "_deg")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _deg";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(end != value.end() - 4) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    return {TweakableState::Success, Magnum::Math::Deg<Magnum::Double>{result}};
+}
+
+std::pair<TweakableState, Magnum::Math::Rad<Magnum::Float>> TweakableParser<Magnum::Math::Rad<Magnum::Float>>::parse(const Containers::ArrayView<const char> value) {
+    char* end;
+    const Magnum::Float result = std::strtof(value, &end);
+
+    if(end == value.begin() || std::find(value.begin(), value.end(), '.') == value.end()) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(!String::viewEndsWith(value, "_radf")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _radf";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(end != value.end() - 5) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    return {TweakableState::Success, Magnum::Math::Rad<Magnum::Float>{result}};
+}
+
+std::pair<TweakableState, Magnum::Math::Rad<Magnum::Double>> TweakableParser<Magnum::Math::Rad<Magnum::Double>>::parse(const Containers::ArrayView<const char> value) {
+    char* end;
+    const Magnum::Double result = std::strtod(value, &end);
+
+    if(end == value.begin() || std::find(value.begin(), value.end(), '.') == value.end()) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(!String::viewEndsWith(value, "_rad")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _rad";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(end != value.end() - 4) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after an angle literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    return {TweakableState::Success, Magnum::Math::Rad<Magnum::Double>{result}};
+}
+
+}}
+#endif

src/Magnum/Math/Angle.h

@@ -282,6 +282,60 @@ template<class T> struct ConfigurationValue<Magnum::Math::Rad<T>> {
     }
 };
 
+#if defined(DOXYGEN_GENERATING_OUTPUT) || defined(CORRADE_TARGET_UNIX) || (defined(CORRADE_TARGET_WINDOWS) && !defined(CORRADE_TARGET_WINDOWS_RT)) || defined(CORRADE_TARGET_EMSCRIPTEN)
+/**
+@tweakableliteral{Magnum::Math::Deg}
+
+Parses the @link Magnum::Math::Literals::operator""_degf @endlink literal.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Deg<Magnum::Float>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Deg<Magnum::Float>> parse(Containers::ArrayView<const char> value);
+};
+
+/**
+@tweakableliteral{Magnum::Math::Deg}
+
+Parses the @link Magnum::Math::Literals::operator""_deg @endlink literal.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Deg<Magnum::Double>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Deg<Magnum::Double>> parse(Containers::ArrayView<const char> value);
+};
+
+/**
+@tweakableliteral{Magnum::Math::Rad}
+
+Parses the @link Magnum::Math::Literals::operator""_radf @endlink literal.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Rad<Magnum::Float>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Rad<Magnum::Float>> parse(Containers::ArrayView<const char> value);
+};
+
+/**
+@tweakableliteral{Magnum::Math::Rad}
+
+Parses the @link Magnum::Math::Literals::operator""_rad @endlink literal.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Rad<Magnum::Double>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Rad<Magnum::Double>> parse(Containers::ArrayView<const char> value);
+};
+
 }}
+#endif
 
 #endif

src/Magnum/Math/Color.cpp

@@ -25,6 +25,12 @@
 
 #include "Color.h"
 
+#if defined(DOXYGEN_GENERATING_OUTPUT) || defined(CORRADE_TARGET_UNIX) || (defined(CORRADE_TARGET_WINDOWS) && !defined(CORRADE_TARGET_WINDOWS_RT)) || defined(CORRADE_TARGET_EMSCRIPTEN)
+#include <cstring>
+#include <Corrade/Utility/String.h>
+#include <Corrade/Utility/Tweakable.h>
+#endif
+
 namespace Magnum { namespace Math {
 
 namespace {
@@ -56,3 +62,129 @@ Corrade::Utility::Debug& operator<<(Corrade::Utility::Debug& debug, const Color4
 }
 
 }}
+
+#if defined(DOXYGEN_GENERATING_OUTPUT) || defined(CORRADE_TARGET_UNIX) || (defined(CORRADE_TARGET_WINDOWS) && !defined(CORRADE_TARGET_WINDOWS_RT)) || defined(CORRADE_TARGET_EMSCRIPTEN)
+namespace Corrade { namespace Utility {
+
+std::pair<TweakableState, Magnum::Math::Color3<Magnum::UnsignedByte>> TweakableParser<Magnum::Math::Color3<Magnum::UnsignedByte>>::parse(const Containers::ArrayView<const char> value) {
+    if(value.size() < 2 || value[0] != '0' || (value[1] != 'x' && value[1] != 'X')) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not a hexadecimal color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    const bool isSrgb = String::viewEndsWith(value, "_srgb");
+    if(!isSrgb && !String::viewEndsWith(value, "_rgb")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _rgb or _srgb";
+        return {TweakableState::Recompile, {}};
+    }
+
+    char* end;
+    const Magnum::UnsignedInt result = std::strtoul(value, &end, 16);
+
+    if(end != value.end() - (isSrgb ? 5 : 4)) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after a color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(value.size() != (isSrgb ? 13 : 12)) {
+        Error{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "doesn't have expected number of digits";
+        return {TweakableState::Error, {}};
+    }
+
+    return {TweakableState::Success,
+        isSrgb ? Magnum::Math::Literals::operator "" _srgb(result) :
+                 Magnum::Math::Literals::operator "" _rgb(result)};
+}
+
+std::pair<TweakableState, Magnum::Math::Color4<Magnum::UnsignedByte>> TweakableParser<Magnum::Math::Color4<Magnum::UnsignedByte>>::parse(const Containers::ArrayView<const char> value) {
+    if(value.size() < 2 || value[0] != '0' || (value[1] != 'x' && value[1] != 'X')) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not a hexadecimal color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    const bool isSrgb = String::viewEndsWith(value, "_srgba");
+    if(!isSrgb && !String::viewEndsWith(value, "_rgba")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _rgba or _srgba";
+        return {TweakableState::Recompile, {}};
+    }
+
+    char* end;
+    const Magnum::UnsignedInt result = std::strtoul(value, &end, 16);
+
+    if(end != value.end() - (isSrgb ? 6 : 5)) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after a color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(value.size() != (isSrgb ? 16 : 15)) {
+        Error{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "doesn't have expected number of digits";
+        return {TweakableState::Error, {}};
+    }
+
+    return {TweakableState::Success,
+        isSrgb ? Magnum::Math::Literals::operator "" _srgba(result) :
+                 Magnum::Math::Literals::operator "" _rgba(result)};
+}
+
+std::pair<TweakableState, Magnum::Math::Color3<Magnum::Float>> TweakableParser<Magnum::Math::Color3<Magnum::Float>>::parse(const Containers::ArrayView<const char> value) {
+    if(value.size() < 2 || value[0] != '0' || (value[1] != 'x' && value[1] != 'X')) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not a hexadecimal color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    const bool isSrgb = String::viewEndsWith(value, "_srgbf");
+    if(!isSrgb && !String::viewEndsWith(value, "_rgbf")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _rgbf or _srgbf";
+        return {TweakableState::Recompile, {}};
+    }
+
+    char* end;
+    const Magnum::UnsignedInt result = std::strtoul(value, &end, 16);
+
+    if(end != value.end() - (isSrgb ? 6 : 5)) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after a color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(value.size() != (isSrgb ? 14 : 13)) {
+        Error{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "doesn't have expected number of digits";
+        return {TweakableState::Error, {}};
+    }
+
+    return {TweakableState::Success,
+        isSrgb ? Magnum::Math::Literals::operator "" _srgbf(result) :
+                 Magnum::Math::Literals::operator "" _rgbf(result)};
+}
+
+std::pair<TweakableState, Magnum::Math::Color4<Magnum::Float>> TweakableParser<Magnum::Math::Color4<Magnum::Float>>::parse(const Containers::ArrayView<const char> value) {
+    if(value.size() < 2 || value[0] != '0' || (value[1] != 'x' && value[1] != 'X')) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not a hexadecimal color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    const bool isSrgb = String::viewEndsWith(value, "_srgbaf");
+    if(!isSrgb && !String::viewEndsWith(value, "_rgbaf")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _rgbaf or _srgbaf";
+        return {TweakableState::Recompile, {}};
+    }
+
+    char* end;
+    const Magnum::UnsignedInt result = std::strtoul(value, &end, 16);
+
+    if(end != value.end() - (isSrgb ? 7 : 6)) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after a color literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(value.size() != (isSrgb ? 17 : 16)) {
+        Error{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "doesn't have expected number of digits";
+        return {TweakableState::Error, {}};
+    }
+
+    return {TweakableState::Success,
+        isSrgb ? Magnum::Math::Literals::operator "" _srgbaf(result) :
+                 Magnum::Math::Literals::operator "" _rgbaf(result)};
+}
+
+}}
+#endif

src/Magnum/Math/Color.h

@@ -1277,11 +1277,77 @@ namespace Implementation {
 }}
 
 namespace Corrade { namespace Utility {
-    /** @configurationvalue{Magnum::Color3} */
-    template<class T> struct ConfigurationValue<Magnum::Math::Color3<T>>: public ConfigurationValue<Magnum::Math::Vector<3, T>> {};
 
-    /** @configurationvalue{Magnum::Color4} */
-    template<class T> struct ConfigurationValue<Magnum::Math::Color4<T>>: public ConfigurationValue<Magnum::Math::Vector<4, T>> {};
+/** @configurationvalue{Magnum::Color3} */
+template<class T> struct ConfigurationValue<Magnum::Math::Color3<T>>: ConfigurationValue<Magnum::Math::Vector<3, T>> {};
+
+/** @configurationvalue{Magnum::Color4} */
+template<class T> struct ConfigurationValue<Magnum::Math::Color4<T>>: ConfigurationValue<Magnum::Math::Vector<4, T>> {};
+
+/**
+@tweakableliteral{Magnum::Math::Color3}
+
+Parses the @link Magnum::Math::Literals::operator""_rgb @endlink and
+@link Magnum::Math::Literals::operator""_srgb @endlink literals.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Color3<Magnum::UnsignedByte>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Color3<Magnum::UnsignedByte>> parse(Containers::ArrayView<const char> value);
+};
+
+#ifndef DOXYGEN_GENERATING_OUTPUT
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Vector3<Magnum::UnsignedByte>>: TweakableParser<Magnum::Math::Color3<Magnum::UnsignedByte>> {};
+#endif
+
+/**
+@tweakableliteral{Magnum::Math::Color4}
+
+Parses the @link Magnum::Math::Literals::operator""_rgba @endlink and
+@link Magnum::Math::Literals::operator""_srgba @endlink literals.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Color4<Magnum::UnsignedByte>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Color4<Magnum::UnsignedByte>> parse(Containers::ArrayView<const char> value);
+};
+
+#ifndef DOXYGEN_GENERATING_OUTPUT
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Vector4<Magnum::UnsignedByte>>: TweakableParser<Magnum::Math::Color4<Magnum::UnsignedByte>> {};
+#endif
+
+/**
+@tweakableliteral{Magnum::Math::Color3}
+
+Parses the @link Magnum::Math::Literals::operator""_rgbf @endlink and
+@link Magnum::Math::Literals::operator""_srgbf @endlink literals.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Color3<Magnum::Float>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Color3<Magnum::Float>> parse(Containers::ArrayView<const char> value);
+};
+
+/**
+@tweakableliteral{Magnum::Math::Color4}
+
+Parses the @link Magnum::Math::Literals::operator""_rgbaf @endlink and
+@link Magnum::Math::Literals::operator""_srgbaf @endlink literals.
+@experimental
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Color4<Magnum::Float>> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Color4<Magnum::Float>> parse(Containers::ArrayView<const char> value);
+};
+
 }}
 
 #endif

src/Magnum/Math/Half.cpp

@@ -28,6 +28,12 @@
 #include <iomanip>
 #include <sstream>
 
+#if defined(DOXYGEN_GENERATING_OUTPUT) || defined(CORRADE_TARGET_UNIX) || (defined(CORRADE_TARGET_WINDOWS) && !defined(CORRADE_TARGET_WINDOWS_RT)) || defined(CORRADE_TARGET_EMSCRIPTEN)
+#include <algorithm>
+#include <Corrade/Utility/String.h>
+#include <Corrade/Utility/TweakableParser.h>
+#endif
+
 namespace Magnum { namespace Math {
 
 Corrade::Utility::Debug& operator<<(Corrade::Utility::Debug& debug, Half value) {
@@ -39,3 +45,31 @@ Corrade::Utility::Debug& operator<<(Corrade::Utility::Debug& debug, Half value)
 }
 
 }}
+
+#if defined(DOXYGEN_GENERATING_OUTPUT) || defined(CORRADE_TARGET_UNIX) || (defined(CORRADE_TARGET_WINDOWS) && !defined(CORRADE_TARGET_WINDOWS_RT)) || defined(CORRADE_TARGET_EMSCRIPTEN)
+namespace Corrade { namespace Utility {
+
+std::pair<TweakableState, Magnum::Math::Half> TweakableParser<Magnum::Math::Half>::parse(const Containers::ArrayView<const char> value) {
+    char* end;
+    const Magnum::Float result = std::strtof(value, &end);
+
+    if(end == value.begin() || std::find(value.begin(), value.end(), '.') == value.end()) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "is not a half literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(!String::viewEndsWith(value, "_h")) {
+        Warning{} << "Utility::TweakableParser:" << std::string{value, value.size()} << "has an unexpected suffix, expected _h";
+        return {TweakableState::Recompile, {}};
+    }
+
+    if(end != value.end() - 2) {
+        Warning{} << "Utility::TweakableParser: unexpected characters" << std::string{const_cast<const char*>(end), value.end()} <<  "after a half literal";
+        return {TweakableState::Recompile, {}};
+    }
+
+    return {TweakableState::Success, Magnum::Math::Half{result}};
+}
+
+}}
+#endif

src/Magnum/Math/Half.h

@@ -163,4 +163,20 @@ MAGNUM_EXPORT Corrade::Utility::Debug& operator<<(Corrade::Utility::Debug& debug
 
 }}
 
+namespace Corrade { namespace Utility {
+
+/**
+@tweakableliteral{Magnum::Math::Half}
+
+Parses the @link Magnum::Math::Literals::operator""_h @endlink literal.
+*/
+template<> struct MAGNUM_EXPORT TweakableParser<Magnum::Math::Half> {
+    TweakableParser() = delete;
+
+    /** @brief Parse the value */
+    static std::pair<TweakableState, Magnum::Math::Half> parse(Containers::ArrayView<const char> value);
+};
+
+}}
+
 #endif

src/Magnum/Math/Test/AngleTest.cpp

@@ -23,9 +23,13 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+#include <cstring>
 #include <sstream>
+#include <Corrade/Containers/ArrayView.h>
 #include <Corrade/TestSuite/Tester.h>
 #include <Corrade/Utility/Configuration.h>
+#include <Corrade/Utility/Format.h>
+#include <Corrade/Utility/TweakableParser.h>
 
 #include "Magnum/Math/Angle.h"
 
@@ -47,6 +51,8 @@ struct AngleTest: Corrade::TestSuite::Tester {
     void debugRad();
     void configurationDeg();
     void configurationRad();
+    template<class T> void tweakable();
+    template<class T> void tweakableError();
 };
 
 typedef Math::Deg<Float> Deg;
@@ -54,6 +60,58 @@ typedef Math::Rad<Float> Rad;
 typedef Math::Deg<Double> Degd;
 typedef Math::Rad<Double> Radd;
 
+using namespace Literals;
+
+namespace {
+
+constexpr struct {
+    const char* name;
+    const char* data;
+    float result;
+} TweakableData[] {
+    {"fixed", "35.0_{}", 35.0f},
+    {"no zero before", ".5_{}",  0.5f},
+    {"no zero after", "35._{}", 35.0f},
+    {"positive", "+35.0_{}", 35.0f},
+    {"negative", "-35.0_{}", -35.0}
+};
+
+constexpr struct {
+    const char* name;
+    const char* data;
+    Corrade::Utility::TweakableState state;
+    const char* error;
+} TweakableErrorData[] {
+    {"empty", "", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser:  is not an angle literal\n"},
+    {"integral", "42_{}", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: 42_{} is not an angle literal\n"},
+    {"garbage after", "42.b_{}", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: unexpected characters b_{} after an angle literal\n"},
+    {"different suffix", "42.0u", Corrade::Utility::TweakableState::Recompile, /* not for double */
+        "Utility::TweakableParser: 42.0u has an unexpected suffix, expected _{}\n"}
+};
+
+template<class> struct TweakableTraits;
+template<> struct TweakableTraits<Deg> {
+    static const char* name() { return "Deg"; }
+    static const char* literal() { return "degf"; }
+};
+template<> struct TweakableTraits<Degd> {
+    static const char* name() { return "Degd"; }
+    static const char* literal() { return "deg"; }
+};
+template<> struct TweakableTraits<Rad> {
+    static const char* name() { return "Rad"; }
+    static const char* literal() { return "radf"; }
+};
+template<> struct TweakableTraits<Radd> {
+    static const char* name() { return "Radd"; }
+    static const char* literal() { return "rad"; }
+};
+
+}
+
 AngleTest::AngleTest() {
     addTests({&AngleTest::construct,
               &AngleTest::constructDefault,
@@ -68,6 +126,20 @@ AngleTest::AngleTest() {
               &AngleTest::debugRad,
               &AngleTest::configurationDeg,
               &AngleTest::configurationRad});
+
+    addInstancedTests<AngleTest>({
+        &AngleTest::tweakable<Deg>,
+        &AngleTest::tweakable<Degd>,
+        &AngleTest::tweakable<Rad>,
+        &AngleTest::tweakable<Radd>},
+        Corrade::Containers::arraySize(TweakableData));
+
+    addInstancedTests<AngleTest>({
+        &AngleTest::tweakableError<Deg>,
+        &AngleTest::tweakableError<Degd>,
+        &AngleTest::tweakableError<Rad>,
+        &AngleTest::tweakableError<Radd>},
+        Corrade::Containers::arraySize(TweakableErrorData));
 }
 
 void AngleTest::construct() {
@@ -162,8 +234,6 @@ void AngleTest::constructCopy() {
 }
 
 void AngleTest::literals() {
-    using namespace Literals;
-
     constexpr auto a = 25.0_deg;
     CORRADE_VERIFY((std::is_same<decltype(a), const Degd>::value));
     CORRADE_COMPARE(Double(a), 25.0);
@@ -234,6 +304,32 @@ void AngleTest::configurationRad() {
     CORRADE_COMPARE(c.value<Rad>("angle"), angle);
 }
 
+template<class T> void AngleTest::tweakable() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseName(Corrade::Utility::formatString("tweakable<{}>", TweakableTraits<T>::name()));
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, TweakableTraits<T>::literal());
+    Corrade::Utility::TweakableState state;
+    T result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<T>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, T(typename T::Type(data.result)));
+}
+
+template<class T> void AngleTest::tweakableError() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseName(Corrade::Utility::formatString("tweakableError<{}>", TweakableTraits<T>::name()));
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, TweakableTraits<T>::literal());
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<T>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, TweakableTraits<T>::literal()));
+    CORRADE_COMPARE(state, data.state);
+}
+
 }}}
 
 CORRADE_TEST_MAIN(Magnum::Math::Test::AngleTest)

src/Magnum/Math/Test/ColorTest.cpp

@@ -27,6 +27,8 @@
 #include <Corrade/TestSuite/Tester.h>
 #include <Corrade/TestSuite/Compare/Numeric.h>
 #include <Corrade/Utility/Configuration.h>
+#include <Corrade/Utility/Format.h>
+#include <Corrade/Utility/Tweakable.h>
 
 #include "Magnum/Math/Color.h"
 
@@ -105,6 +107,24 @@ struct ColorTest: Corrade::TestSuite::Tester {
     void debug();
     void debugUb();
     void configuration();
+
+    void tweakableRgb();
+    void tweakableSrgb();
+    void tweakableRgbf();
+    void tweakableSrgbf();
+    void tweakableRgba();
+    void tweakableSrgba();
+    void tweakableRgbaf();
+    void tweakableSrgbaf();
+
+    void tweakableErrorRgb();
+    void tweakableErrorSrgb();
+    void tweakableErrorRgba();
+    void tweakableErrorSrgba();
+    void tweakableErrorRgbf();
+    void tweakableErrorSrgbf();
+    void tweakableErrorRgbaf();
+    void tweakableErrorSrgbaf();
 };
 
 typedef Math::Vector3<Float> Vector3;
@@ -117,6 +137,44 @@ typedef Math::Color4<UnsignedByte> Color4ub;
 
 typedef Math::Deg<Float> Deg;
 
+using namespace Literals;
+
+namespace {
+
+const struct {
+    const char* name;
+    const char* dataRgb;
+    const char* dataRgba;
+    Color4 result;
+    Color4 resultSrgba;
+    Color4ub resultUb;
+} TweakableData[] {
+    {"lowercase", "0xff3366_{}", "0xff3366aa_{}", 0xff3366aa_rgbaf, 0xff3366aa_srgbaf, 0xff3366aa_rgba},
+    {"uppercase", "0XFF3366_{}", "0XFF3366AA_{}", 0xff3366aa_rgbaf, 0xff3366aa_srgbaf, 0xff3366aa_rgba}
+};
+
+constexpr struct {
+    const char* name;
+    const char* data;
+    Corrade::Utility::TweakableState state;
+    const char* error;
+} TweakableErrorData[] {
+    {"empty", "", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser:  is not a hexadecimal color literal\n"},
+    {"char", "'a'", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: 'a' is not a hexadecimal color literal\n"},
+    {"not hex", "{}_{}", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: {0}_{2}{1} is not a hexadecimal color literal\n"},
+    {"garbage after", "0x{}._{}", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: unexpected characters ._{2}{1} after a color literal\n"},
+    {"different suffix", "0x{}f", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: 0x{0}f has an unexpected suffix, expected _{1} or _s{1}\n"},
+    {"bad size", "0x333_{1}", Corrade::Utility::TweakableState::Error,
+        "Utility::TweakableParser: 0x333_{2}{1} doesn't have expected number of digits\n"},
+};
+
+}
+
 ColorTest::ColorTest() {
     addTests({&ColorTest::construct,
               &ColorTest::constructDefault,
@@ -157,6 +215,26 @@ ColorTest::ColorTest() {
               &ColorTest::debug,
               &ColorTest::debugUb,
               &ColorTest::configuration});
+
+    addInstancedTests({&ColorTest::tweakableRgb,
+                       &ColorTest::tweakableSrgb,
+                       &ColorTest::tweakableRgba,
+                       &ColorTest::tweakableSrgba,
+                       &ColorTest::tweakableRgbf,
+                       &ColorTest::tweakableSrgbf,
+                       &ColorTest::tweakableRgbaf,
+                       &ColorTest::tweakableSrgbaf},
+                      Corrade::Containers::arraySize(TweakableData));
+
+    addInstancedTests({&ColorTest::tweakableErrorRgb,
+                       &ColorTest::tweakableErrorSrgb,
+                       &ColorTest::tweakableErrorRgba,
+                       &ColorTest::tweakableErrorSrgba,
+                       &ColorTest::tweakableErrorRgbf,
+                       &ColorTest::tweakableErrorSrgbf,
+                       &ColorTest::tweakableErrorRgbaf,
+                       &ColorTest::tweakableErrorSrgbaf},
+                      Corrade::Containers::arraySize(TweakableErrorData));
 }
 
 void ColorTest::construct() {
@@ -365,8 +443,6 @@ void ColorTest::data() {
 }
 
 void ColorTest::literals() {
-    using namespace Literals;
-
     constexpr Color3ub a = 0x33b27f_rgb;
     CORRADE_COMPARE(a, (Color3ub{0x33, 0xb2, 0x7f}));
 
@@ -423,8 +499,6 @@ void ColorTest::colors() {
 }
 
 void ColorTest::hue() {
-    using namespace Literals;
-
     CORRADE_COMPARE(Color3::fromHsv( 27.0_degf, 1.0f, 1.0f), (Color3{1.0f, 0.45f, 0.0f}));
     CORRADE_COMPARE(Color3::fromHsv( 86.0_degf, 1.0f, 1.0f), (Color3{0.566667f, 1.0f, 0.0f}));
     CORRADE_COMPARE(Color3::fromHsv(134.0_degf, 1.0f, 1.0f), (Color3{0.0f, 1.0f, 0.233333f}));
@@ -453,8 +527,6 @@ void ColorTest::hue() {
 }
 
 void ColorTest::saturation() {
-    using namespace Literals;
-
     CORRADE_COMPARE(Color3::fromHsv(0.0_degf, 0.702f, 1.0f), (Color3{1.0f, 0.298f, 0.298f}));
     CORRADE_COMPARE((Color3{1.0f, 0.298f, 0.298f}).saturation(), 0.702f);
 
@@ -476,8 +548,6 @@ void ColorTest::saturation() {
 }
 
 void ColorTest::value() {
-    using namespace Literals;
-
     CORRADE_COMPARE(Color3::fromHsv(0.0_degf, 1.0f, 0.522f), (Color3{0.522f, 0.0f, 0.0f}));
     CORRADE_COMPARE((Color3{0.522f, 0.0f, 0.0f}).value(), 0.522f);
 
@@ -499,8 +569,6 @@ void ColorTest::value() {
 }
 
 void ColorTest::hsv() {
-    using namespace Literals;
-
     CORRADE_COMPARE(Color3::fromHsv(std::make_tuple(230.0_degf, 0.749f, 0.427f)),
         (Color3{0.107177f, 0.160481f, 0.427f}));
     CORRADE_COMPARE(Color3::fromHsv(230.0_degf, 0.749f, 0.427f),
@@ -552,8 +620,6 @@ void ColorTest::hsv() {
 }
 
 void ColorTest::fromHsvHueOverflow() {
-    using namespace Literals;
-
     CORRADE_COMPARE(Color3::fromHsv( 27.0_degf - 360.0_degf, 1.0f, 1.0f), (Color3{1.0f, 0.45f, 0.0f}));
     CORRADE_COMPARE(Color3::fromHsv( 86.0_degf - 360.0_degf, 1.0f, 1.0f), (Color3{0.566667f, 1.0f, 0.0f}));
     CORRADE_COMPARE(Color3::fromHsv(134.0_degf - 360.0_degf, 1.0f, 1.0f), (Color3{0.0f, 1.0f, 0.233333f}));
@@ -570,8 +636,6 @@ void ColorTest::fromHsvHueOverflow() {
 }
 
 void ColorTest::fromHsvDefaultAlpha() {
-    using namespace Literals;
-
     CORRADE_COMPARE(Color4::fromHsv(std::make_tuple(230.0_degf, 0.749f, 0.427f)),
         (Color4{0.107177f, 0.160481f, 0.427f, 1.0f}));
     CORRADE_COMPARE(Color4::fromHsv(230.0_degf, 0.749f, 0.427f),
@@ -697,8 +761,6 @@ void ColorTest::srgbMonotonic() {
 }
 
 void ColorTest::srgbLiterals() {
-    using namespace Literals;
-
     constexpr Math::Vector3<UnsignedByte> a = 0x33b27f_srgb;
     CORRADE_COMPARE(a, (Math::Vector3<UnsignedByte>{0x33, 0xb2, 0x7f}));
 
@@ -808,8 +870,6 @@ void ColorTest::debug() {
 }
 
 void ColorTest::debugUb() {
-    using namespace Magnum::Math::Literals;
-
     std::ostringstream o;
     Debug(&o) << 0x123456_rgb << 0x789abc_rgb;
     CORRADE_COMPARE(o.str(), "#123456 #789abc\n");
@@ -837,6 +897,198 @@ void ColorTest::configuration() {
     CORRADE_COMPARE(c.value<Color4>("color4"), color4);
 }
 
+void ColorTest::tweakableRgb() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgb, "rgb");
+    Corrade::Utility::TweakableState state;
+    Color3ub result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Color3ub>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.resultUb.rgb());
+}
+
+void ColorTest::tweakableSrgb() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgb, "srgb");
+    Corrade::Utility::TweakableState state;
+    Math::Vector3<UnsignedByte> result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Math::Vector3<UnsignedByte>>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.resultUb.rgb());
+}
+
+void ColorTest::tweakableRgba() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgba, "rgba");
+    Corrade::Utility::TweakableState state;
+    Color4ub result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Color4ub>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.resultUb);
+}
+
+void ColorTest::tweakableSrgba() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgba, "srgba");
+    Corrade::Utility::TweakableState state;
+    Math::Vector4<UnsignedByte> result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Math::Vector4<UnsignedByte>>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.resultUb);
+}
+
+void ColorTest::tweakableRgbf() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgb, "rgbf");
+    Corrade::Utility::TweakableState state;
+    Color3 result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Color3>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.result.rgb());
+}
+
+void ColorTest::tweakableSrgbf() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgb, "srgbf");
+    Corrade::Utility::TweakableState state;
+    Color3 result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Color3>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.resultSrgba.rgb());
+}
+
+void ColorTest::tweakableRgbaf() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgba, "rgbaf");
+    Corrade::Utility::TweakableState state;
+    Color4 result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Color4>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.result);
+}
+
+void ColorTest::tweakableSrgbaf() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.dataRgba, "srgbaf");
+    Corrade::Utility::TweakableState state;
+    Color4 result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Color4>::parse({input.data(), input.size()});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.resultSrgba);
+}
+
+void ColorTest::tweakableErrorRgb() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366", "rgb");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Color3ub>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366", "rgb", ""));
+    CORRADE_COMPARE(state, data.state);
+}
+
+void ColorTest::tweakableErrorSrgb() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366", "srgb");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Math::Vector3<UnsignedByte>>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366", "rgb", "s"));
+    CORRADE_COMPARE(state, data.state);
+}
+
+void ColorTest::tweakableErrorRgba() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366aa", "rgba");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Color4ub>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366aa", "rgba", ""));
+    CORRADE_COMPARE(state, data.state);
+}
+
+void ColorTest::tweakableErrorSrgba() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366aa", "srgba");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Math::Vector4<UnsignedByte>>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366aa", "rgba", "s"));
+    CORRADE_COMPARE(state, data.state);
+}
+
+void ColorTest::tweakableErrorRgbf() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366", "rgbf");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Color3>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366", "rgbf", ""));
+    CORRADE_COMPARE(state, data.state);
+}
+
+void ColorTest::tweakableErrorSrgbf() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366", "srgbf");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Color3>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366", "rgbf", "s"));
+    CORRADE_COMPARE(state, data.state);
+}
+
+void ColorTest::tweakableErrorRgbaf() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366aa", "rgbaf");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Color4>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366aa", "rgbaf", ""));
+    CORRADE_COMPARE(state, data.state);
+}
+
+void ColorTest::tweakableErrorSrgbaf() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    std::string input = Corrade::Utility::formatString(data.data, "ff3366aa", "srgbaf");
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Color4>::parse({input.data(), input.size()}).first;
+    CORRADE_COMPARE(out.str(), Corrade::Utility::formatString(data.error, "ff3366aa", "rgbaf", "s"));
+    CORRADE_COMPARE(state, data.state);
+}
+
 }}}
 
 CORRADE_TEST_MAIN(Magnum::Math::Test::ColorTest)

src/Magnum/Math/Test/HalfTest.cpp

@@ -23,8 +23,11 @@
     DEALINGS IN THE SOFTWARE.
 */
 
+#include <cstring>
+#include <algorithm>
 #include <sstream>
 #include <Corrade/TestSuite/Tester.h>
+#include <Corrade/Utility/Tweakable.h>
 
 #include "Magnum/Math/Half.h"
 #include "Magnum/Math/Vector3.h"
@@ -59,6 +62,8 @@ struct HalfTest: Corrade::TestSuite::Tester {
 
     void literal();
     void debug();
+    void tweakable();
+    void tweakableError();
 
     private:
         /* Naive / ground-truth packing helpers */
@@ -79,6 +84,42 @@ struct HalfTest: Corrade::TestSuite::Tester {
 
 typedef Math::Constants<Float> Constants;
 
+using namespace Literals;
+
+namespace {
+
+const struct {
+    const char* name;
+    const char* data;
+    Half result;
+} TweakableData[] {
+    {"fixed", "35.0_h", 35.0_h},
+    {"no zero before", ".5_h",  0.5_h},
+    {"no zero after", "35._h", 35.0_h},
+    {"exponential positive", "3.5e+1_h", 3.5e+1_h},
+    {"exponential negative", "350.0e-1_h", 350.0e-1_h},
+    {"positive", "+35.0_h", +35.0_h},
+    {"negative", "-35.0_h", -35.0_h}
+};
+
+constexpr struct {
+    const char* name;
+    const char* data;
+    Corrade::Utility::TweakableState state;
+    const char* error;
+} TweakableErrorData[] {
+    {"empty", "", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser:  is not a half literal\n"},
+    {"integral", "42_h", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: 42_h is not a half literal\n"},
+    {"garbage after", "42.b_h", Corrade::Utility::TweakableState::Recompile,
+        "Utility::TweakableParser: unexpected characters b_h after a half literal\n"},
+    {"different suffix", "42.0u", Corrade::Utility::TweakableState::Recompile, /* not for double */
+        "Utility::TweakableParser: 42.0u has an unexpected suffix, expected _h\n"}
+};
+
+}
+
 HalfTest::HalfTest() {
     addTests({&HalfTest::unpack,
               &HalfTest::pack});
@@ -109,6 +150,12 @@ HalfTest::HalfTest() {
               &HalfTest::literal,
               &HalfTest::debug});
 
+    addInstancedTests({&HalfTest::tweakable},
+                      Corrade::Containers::arraySize(TweakableData));
+
+    addInstancedTests({&HalfTest::tweakableError},
+                      Corrade::Containers::arraySize(TweakableErrorData));
+
     /* Calculate tables for table-based benchmark */
     _mantissaTable[0] = 0;
     for(std::size_t i = 1; i != 1024; ++i)
@@ -597,16 +644,12 @@ void HalfTest::negation() {
 }
 
 void HalfTest::literal() {
-    using namespace Literals;
-
     Half a = 3.5_h;
     CORRADE_COMPARE(a, Half{UnsignedShort(0x4300)});
     CORRADE_COMPARE(a, Half{3.5f});
 }
 
 void HalfTest::debug() {
-    using namespace Literals;
-
     std::ostringstream out;
 
     Debug{&out} << -36.41_h << Half{Constants::inf()}
@@ -618,6 +661,28 @@ void HalfTest::debug() {
     #endif
 }
 
+void HalfTest::tweakable() {
+    auto&& data = TweakableData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+    Corrade::Utility::TweakableState state;
+    Half result;
+    std::tie(state, result) = Corrade::Utility::TweakableParser<Half>::parse({data.data, std::strlen(data.data)});
+    CORRADE_COMPARE(state, Corrade::Utility::TweakableState::Success);
+    CORRADE_COMPARE(result, data.result);
+}
+
+void HalfTest::tweakableError() {
+    auto&& data = TweakableErrorData[testCaseInstanceId()];
+    setTestCaseDescription(data.name);
+
+    std::ostringstream out;
+    Warning redirectWarning{&out};
+    Error redirectError{&out};
+    Corrade::Utility::TweakableState state = Corrade::Utility::TweakableParser<Half>::parse({data.data, std::strlen(data.data)}).first;
+    CORRADE_COMPARE(out.str(), data.error);
+    CORRADE_COMPARE(state, data.state);
+}
+
 }}}
 
 CORRADE_TEST_MAIN(Magnum::Math::Test::HalfTest)