@文心快码'constexpr' needed for in-class initialization of static data member 文心快码 1. 解释constexpr的含义和用途 constexpr是C++11引入的一个关键字,用于声明可以在编译时求值的变量、函数或者对象的构造函数。使用constexpr声明的变量或函数返回值必须在编译时就能确定其值,这样的变量或函数通常用于优化性能...
In file included from /bla/hardware/Arduino_STM32/STM32F1/libraries/STM32ADC/examples/SingleConversionInterrupt/SingleConversionInterrupt.ino:1:0: /bla/hardware/Arduino_STM32/STM32F1/libraries/STM32ADC/src/STM32ADC.h:155:40: error: 'constexpr' needed for in-class initialization of static data...
In C++11, non-staticdata members,static constexprdata members, andstatic constdata members of integral or enumeration type may be initialized in the class declaration. e.g. struct X { int i=5; const float f=3.12f; static const int j=42; static constexpr float g=9.5f; };...
This was the last feature that we needed to implement for C++11 constexpr support and we’re excited to ship it with Update 1. We should extend kudos to Tanveer Gani for the herculean work he’s done to make this feature ship with Update 1. Because of his work, Update 1 will be ...
apply consistently: For common cases, we shouldn't have a gazillion of rules. Doing something excep should require reading the fine print, and the main rules should make it obvious what's an exceptional case (e.g. by omitting the specific keywords that would be needed for exceptional cases)...
The class does not have anyvirtual base class. For aconstexprconstructor that is neither defaulted nor templated, if no argument values exist such that an invocation of the function could be an evaluated subexpression of the initialization full-expression of some object subject toconstant expression...
but an empty class instead. So it doesn’t contains an indeterminate value even when default-initialized. On the other hand, libc++ & MSVC STL’sstd::array<T, 0>do store a built-in array ofchar, so default-initialization is no suitable forco...
[regression] [worked-in:16.10.0 preview] constexpr with std::string and static variable gives empty string. constexpr from function seems to work. Example: #include <string> #include <iostream> class Value { public: inline constexpr static std::string s_value{ "valueStatic"...
In the beginning, we experienced an issue with the early initialization of static variables in the init priority. This involved utilizing various pieces of code, such asstruct Type<int> { static int max; };for a specific purpose, globalstatic int x = Type<int>::max;, and other early cod...
For pybind11, we can use the py::return_value_policy::copy as described here .def_readonly_static("NAN", &Class::NaN, py::return_value_policy::copy, "math::Vector2(NaN, NaN)") If that seems reasonable, I can push my changes to this PR. 👍 1 Contributor Author jwnimmer-tri...