enumclass.h File Reference

G3D Innovation Engine http://casual-effects.com/g3d Copyright 2000-2019, Morgan McGuire All rights reserved Available under the BSD License. More...

Namespaces
	G3D
	G3D::_internal

Macros
#define	G3D_BEGIN_ENUM_CLASS_DECLARATION(ClassName, ...)
#define	G3D_DECLARE_ENUM_CLASS(ClassName, ...)
	More...
#define	G3D_DECLARE_ENUM_CLASS_HASHCODE(Classname)
	Must be used at top level (i.e., not inside a class or namespace), with a fully qualified class name. More...
#define	G3D_DECLARE_ENUM_CLASS_METHODS(Classname)
	Creates a series of methods that turn a class into a scoped enumeration. More...
#define	G3D_END_ENUM_CLASS_DECLARATION()   }

Functions
template<class EnumClass , class EnumClassValue >
void	G3D::enumToJavaScriptDeclaration (TextOutput &t)
	Generates JavaScript source code defining an enum equivalent to EnumClass. More...
const char **	G3D::_internal::smartEnumParseNames (const char *enumValList)

Detailed Description

G3D Innovation Engine http://casual-effects.com/g3d Copyright 2000-2019, Morgan McGuire All rights reserved Available under the BSD License.

Macro Definition Documentation

G3D_BEGIN_ENUM_CLASS_DECLARATION

#define G3D_BEGIN_ENUM_CLASS_DECLARATION	(		ClassName,
			...
	)

Value:

class ClassName {\
public:\
    enum Value {\
        __VA_ARGS__\
    } value;\
\
    /* The static variables here may be duplicated in different shared object binaries (DLLs), but that's ok--we only depend on their values, not their uniqueness.  See also http://stackoverflow.com/questions/11962918/local-static-variable-is-instantiated-multiple-times-why */\
    static const char* toString(int i, Value& v) {\
        static const char** str = G3D::_internal::smartEnumParseNames(#__VA_ARGS__);\
        static const Value val[] = {__VA_ARGS__};\
        const char* s = str[i];\
        if (s) { v = val[i]; }\
        return s;\
    }\
\
    G3D_DECLARE_ENUM_CLASS_METHODS(ClassName);

G3D_BEGIN_ENUM_CLASS_DECLARATION(Day, SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY);
   // Put extra methods here, e.g., 
   Value nextValue() { ... }
G3D_END_ENUM_CLASS_DECLARATION();
}
G3D_DECLARE_ENUM_CLASS_HASHCODE(Foo::Day);

See also

G3D_DECLARE_ENUM_CLASS, G3D_END_ENUM_CLASS_DECLARATION

G3D_DECLARE_ENUM_CLASS

#define G3D_DECLARE_ENUM_CLASS	(		ClassName,
			...
	)

Value:

G3D_BEGIN_ENUM_CLASS_DECLARATION(ClassName, __VA_ARGS__);\
    G3D_END_ENUM_CLASS_DECLARATION();

// Arguments may not have initializer expressions.  Arguments may contain comments.
// Namespaces aren't *required*, this example just shows how to use them.
namespace Foo {
   G3D_DECLARE_ENUM_CLASS(Day, SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY);
}
G3D_DECLARE_ENUM_CLASS_HASHCODE(Foo::Day);
...

using namespace Foo;
// Example use of the smart enum
Day d = Day::TUESDAY;
Day d2("SATURDAY");
Any a(d);
d = a;
printf("%s = %d\n", d.toString(), d.value);

Provides these methods:

const char* toString()
arithmetic operators
static int count()
static Value nthValue(n)

See also

G3D_DECLARE_ENUM_CLASS_METHODS, G3D_DECLARE_ENUM_CLASS_HASHCODE, G3D::enumToJavaScriptDeclaration, G3D_BEGIN_ENUM_CLASS_DECLARATION

G3D_DECLARE_ENUM_CLASS_HASHCODE

#define G3D_DECLARE_ENUM_CLASS_HASHCODE

(

Classname

)

Value:

template <> struct HashTrait<Classname::Value>                                              \
{                                                                                           \
    static size_t hashCode(Classname::Value key) { return static_cast<size_t>(key); }       \
};                                                                                          \
                                                                                            \
template <> struct HashTrait<Classname>                                                     \
{                                                                                           \
    static size_t hashCode(Classname key) { return static_cast<size_t>(key.hashCode()); }   \
};

Must be used at top level (i.e., not inside a class or namespace), with a fully qualified class name.

G3D_DECLARE_ENUM_CLASS_METHODS

#define G3D_DECLARE_ENUM_CLASS_METHODS

(

Classname

)

Creates a series of methods that turn a class into a scoped enumeration.

Example of use:

class Resource {
public:
  enum Value {FUEL, FOOD, WATER} value;
  
  // i is the position the enum value in Value (not the enum value itself)
  static const char* toString(int i, Value& v) {
      static const char* str[] = {"FUEL", "FOOD", "WATER", nullptr}; // Whatever your enum values are
      static const Value val[] = {FUEL, FOOD, WATER};             // Whatever your enum values are
      const char* s = str[i];
      if (s) {
          v = val[i];
      }
      return s;
  }

  G3D_DECLARE_ENUM_CLASS_METHODS(Resource);
};
G3D_DECLARE_ENUM_CLASS_HASHCODE(Resource);

Supports enumerations with initializer values.

Extends the "Intelligent Enum" design pattern http://www.codeguru.com/cpp/cpp/cpp_mfc/article.php/c4001/

Enum classes are initialized to their zero value by default.

See G3D-app/GKey.h and G3D-base/WrapMode for an example.

See also

G3D_DECLARE_ENUM_CLASS_HASHCODE

G3D_END_ENUM_CLASS_DECLARATION

#define G3D_END_ENUM_CLASS_DECLARATION

(

)

}

See also

G3D_BEGIN_ENUM_CLASS_DECLARATION