nameof_module/doc/limitations.md

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# Nameof
* If argument does not have name, occurs the compilation error `"Expression does not have a name."`.
# Nameof Type
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* To check is nameof type supported compiler use macro `NAMEOF_TYPE_SUPPORTED` or constexpr constant `nameof::is_nameof_type_supported`.
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* This library uses a compiler-specific hack (based on `__PRETTY_FUNCTION__` / `__FUNCSIG__`), which works on Clang >= 5, MSVC >= 15.3 and GCC >= 7.
* Nameof type returns compiler-specific type name.
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* If argument does not have name, occurs the compilation error `"Expression does not have a name."`.
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# Nameof Enum
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* To check is nameof enum supported compiler use macro `NAMEOF_ENUM_SUPPORTED` or constexpr constant `nameof::is_nameof_enum_supported`.
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* This library uses a compiler-specific hack (based on `__PRETTY_FUNCTION__` / `__FUNCSIG__`), which works on Clang >= 5, MSVC >= 15.3 and GCC >= 9.
* Enum can't reflect if the enum is a forward declaration.
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* Enum value must be in range `[NAMEOF_ENUM_RANGE_MIN, NAMEOF_ENUM_RANGE_MAX]`. By default `NAMEOF_ENUM_RANGE_MIN = -128`, `NAMEOF_ENUM_RANGE_MAX = 128`.
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* If need another range for all enum types by default, redefine the macro `NAMEOF_ENUM_RANGE_MIN` and `NAMEOF_ENUM_RANGE_MAX`.
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```cpp
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#define NAMEOF_ENUM_RANGE_MIN 0
#define NAMEOF_ENUM_RANGE_MAX 256
#include <nameof.hpp>
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```
* If need another range for specific enum type, add specialization `enum_range` for necessary enum type.
```cpp
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#include <nameof.hpp>
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enum number { one = 100, two = 200, three = 300 };
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namespace nameof {
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template <>
struct enum_range<number> {
static constexpr int min = 100;
static constexpr int max = 300;
};
}
```
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* Nameof enum obtains the first defined value enums, and won't work if value are aliased.
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```cpp
enum ShapeKind {
ConvexBegin = 0,
Box = 0, // Won't work.
Sphere = 1,
ConvexEnd = 2,
Donut = 2, // Won't work too.
Banana = 3,
COUNT = 4,
};
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// nameof::nameof_enum(ShapeKind::Box) -> "ConvexBegin"
// NAMEOF_ENUM(ShapeKind::Box) -> "ConvexBegin"
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```
Work around the issue:
```cpp
enum ShapeKind {
// Convex shapes, see ConvexBegin and ConvexEnd below.
Box = 0,
Sphere = 1,
// Non-convex shapes.
Donut = 2,
Banana = 3,
COUNT = Banana + 1,
// Non-reflected aliases.
ConvexBegin = Box,
ConvexEnd = Sphere + 1,
};
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// nameof::nameof_enum(ShapeKind::Box) -> "Box"
// NAMEOF_ENUM(ShapeKind::Box) -> "Box"
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// Non-reflected aliases.
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// nameof::nameof_enum(ShapeKind::ConvexBegin) -> "Box"
// NAMEOF_ENUM(ShapeKind::ConvexBegin) -> "Box"
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```