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#include <glib-object.h>
            GEnumClass;
            GFlagsClass;
#define     G_ENUM_CLASS_TYPE               (class)
#define     G_ENUM_CLASS_TYPE_NAME          (class)
#define     G_TYPE_IS_ENUM                  (type)
#define     G_ENUM_CLASS                    (class)
#define     G_IS_ENUM_CLASS                 (class)
#define     G_TYPE_IS_FLAGS                 (type)
#define     G_FLAGS_CLASS                   (class)
#define     G_IS_FLAGS_CLASS                (class)
#define     G_FLAGS_CLASS_TYPE              (class)
#define     G_FLAGS_CLASS_TYPE_NAME         (class)
            GEnumValue;
            GFlagsValue;
GEnumValue* g_enum_get_value                (GEnumClass *enum_class,
                                             gint value);
GEnumValue* g_enum_get_value_by_name        (GEnumClass *enum_class,
                                             const gchar *name);
GEnumValue* g_enum_get_value_by_nick        (GEnumClass *enum_class,
                                             const gchar *nick);
GFlagsValue* g_flags_get_first_value        (GFlagsClass *flags_class,
                                             guint value);
GFlagsValue* g_flags_get_value_by_name      (GFlagsClass *flags_class,
                                             const gchar *name);
GFlagsValue* g_flags_get_value_by_nick      (GFlagsClass *flags_class,
                                             const gchar *nick);
GType       g_enum_register_static          (const gchar *name,
                                             const GEnumValue *const_static_values);
GType       g_flags_register_static         (const gchar *name,
                                             const GFlagsValue *const_static_values);
void        g_enum_complete_type_info       (GType g_enum_type,
                                             GTypeInfo *info,
                                             const GEnumValue *const_values);
void        g_flags_complete_type_info      (GType g_flags_type,
                                             GTypeInfo *info,
                                             const GFlagsValue *const_values);
The GLib type system provides fundamental types for enumeration and flags types. (Flags types
are like enumerations, but allow their values to be combined by bitwise or). A registered 
enumeration or flags type associates a name and a nickname with each allowed value, and 
the methods g_enum_get_value_by_name(), g_enum_get_value_by_nick(), g_flags_get_value_by_name()
and g_flags_get_value_by_nick() can look up values by their name or nickname.
When an enumeration or flags type is registered with the GLib type system, it can
be used as value type for object properties, using g_param_spec_enum() or 
g_param_spec_flags().
GObject ships with a utility called glib-mkenums that can construct suitable type registration functions from C enumeration definitions.
typedef struct {
  GTypeClass  g_type_class;
  gint	      minimum;
  gint	      maximum;
  guint	      n_values;
  GEnumValue *values;
} GEnumClass;
The class of an enumeration type holds information about its possible values.
| GTypeClass g_type_class; | the parent class | 
| gint minimum; | the smallest possible value. | 
| gint maximum; | the largest possible value. | 
| guint n_values; | the number of possible values. | 
| GEnumValue * values; | an array of GEnumValue structs describing the individual values. | 
typedef struct {
  GTypeClass   g_type_class;
  
  guint	       mask;
  guint	       n_values;
  GFlagsValue *values;
} GFlagsClass;
The class of a flags type holds information about its possible values.
| GTypeClass g_type_class; | the parent class | 
| guint mask; | a mask covering all possible values. | 
| guint n_values; | the number of possible values. | 
| GFlagsValue * values; | an array of GFlagsValue structs describing the individual values. | 
#define G_ENUM_CLASS_TYPE(class) (G_TYPE_FROM_CLASS (class))
Returns the type identifier from a given GEnumClass structure.
| class: | a GEnumClass | 
#define G_ENUM_CLASS_TYPE_NAME(class) (g_type_name (G_ENUM_CLASS_TYPE (class)))
Returns the static type name from a given GEnumClass structure.
| class: | a GEnumClass | 
#define G_TYPE_IS_ENUM(type) (G_TYPE_FUNDAMENTAL (type) == G_TYPE_ENUM)
Returns whether type "is a" G_TYPE_ENUM.
| type: | a GType ID. | 
#define G_ENUM_CLASS(class) (G_TYPE_CHECK_CLASS_CAST ((class), G_TYPE_ENUM, GEnumClass))
Casts a derived GEnumClass structure into a GEnumClass structure.
| class: | a valid GEnumClass | 
#define G_IS_ENUM_CLASS(class) (G_TYPE_CHECK_CLASS_TYPE ((class), G_TYPE_ENUM))
Checks whether class "is a" valid GEnumClass structure of type G_TYPE_ENUM
or derived.
| class: | a GEnumClass | 
#define G_TYPE_IS_FLAGS(type) (G_TYPE_FUNDAMENTAL (type) == G_TYPE_FLAGS)
Returns whether type "is a" G_TYPE_FLAGS.
| type: | a GType ID. | 
#define G_FLAGS_CLASS(class) (G_TYPE_CHECK_CLASS_CAST ((class), G_TYPE_FLAGS, GFlagsClass))
Casts a derived GFlagsClass structure into a GFlagsClass structure.
| class: | a valid GFlagsClass | 
#define G_IS_FLAGS_CLASS(class) (G_TYPE_CHECK_CLASS_TYPE ((class), G_TYPE_FLAGS))
Checks whether class "is a" valid GFlagsClass structure of type G_TYPE_FLAGS
or derived.
| class: | a GFlagsClass | 
#define G_FLAGS_CLASS_TYPE(class) (G_TYPE_FROM_CLASS (class))
Returns the type identifier from a given GFlagsClass structure.
| class: | a GFlagsClass | 
#define G_FLAGS_CLASS_TYPE_NAME(class) (g_type_name (G_FLAGS_CLASS_TYPE (class)))
Returns the static type name from a given GFlagsClass structure.
| class: | a GFlagsClass | 
typedef struct {
  gint	 value;
  gchar *value_name;
  gchar *value_nick;
} GEnumValue;
A structure which contains a single enum value, it's name, and it's nickname.
typedef struct {
  guint	 value;
  gchar *value_name;
  gchar *value_nick;
} GFlagsValue;
A structure which contains a single flags value, it's name, and it's nickname.
GEnumValue* g_enum_get_value (GEnumClass *enum_class, gint value);
Returns the GEnumValue for a value.
| enum_class: | a GEnumClass | 
| value: | the value to look up | 
| Returns : | the GEnumValue for value, orNULLifvalueis not 
a member of the enumeration | 
GEnumValue* g_enum_get_value_by_name (GEnumClass *enum_class, const gchar *name);
Looks up a GEnumValue by name.
| enum_class: | a GEnumClass | 
| name: | the name to look up | 
| Returns : | the GEnumValue with name name, orNULLif the enumeration doesn'
t have a member with that name | 
GEnumValue* g_enum_get_value_by_nick (GEnumClass *enum_class, const gchar *nick);
Looks up a GEnumValue by nickname.
| enum_class: | a GEnumClass | 
| nick: | the nickname to look up | 
| Returns : | the GEnumValue with nickname nick, orNULLif the enumeration doesn'
t have a member with that nickname | 
GFlagsValue* g_flags_get_first_value (GFlagsClass *flags_class, guint value);
Returns the first GFlagsValue which is set in value.
| flags_class: | a GFlagsClass | 
| value: | the value | 
| Returns : | the first GFlagsValue which is set in value, orNULLif none is set | 
GFlagsValue* g_flags_get_value_by_name (GFlagsClass *flags_class, const gchar *name);
Looks up a GFlagsValue by name.
| flags_class: | a GFlagsClass | 
| name: | the name to look up | 
| Returns : | the GFlagsValue with name name, orNULLif there is no flag with
that name | 
GFlagsValue* g_flags_get_value_by_nick (GFlagsClass *flags_class, const gchar *nick);
Looks up a GFlagsValue by nickname.
| flags_class: | a GFlagsClass | 
| nick: | the nickname to look up | 
| Returns : | the GFlagsValue with nickname nick, orNULLif there is no flag
with that nickname | 
GType g_enum_register_static (const gchar *name, const GEnumValue *const_static_values);
Registers a new static enumeration type with the name name. 
It is normally more convenient to let glib-mkenums 
generate a my_enum_get_type() function from a usual C enumeration definition
than to write one yourself using g_enum_register_static().
| name: | A nul-terminated string used as the name of the new type. | 
| const_static_values: | An array of GEnumValue structs for the possible enumeration values. The array is terminated by a struct with all members being 0. | 
| Returns : | The new type identifier. | 
GType g_flags_register_static (const gchar *name, const GFlagsValue *const_static_values);
Registers a new static flags type with the name name. 
It is normally more convenient to let glib-mkenums 
generate a my_flags_get_type() function from a usual C enumeration definition
than to write one yourself using g_flags_register_static().
| name: | A nul-terminated string used as the name of the new type. | 
| const_static_values: | An array of GFlagsValue structs for the possible flags values. The array is terminated by a struct with all members being 0. | 
| Returns : | The new type identifier. | 
void g_enum_complete_type_info (GType g_enum_type, GTypeInfo *info, const GEnumValue *const_values);
This function is meant to be called from the complete_type_info() function 
of a GTypePlugin implementation, as in the following example:
static void
my_enum_complete_type_info (GTypePlugin     *plugin,
                            GType            g_type,
                            GTypeInfo       *info,
                            GTypeValueTable *value_table)
{
  static const GEnumValue values[] = {
    { MY_ENUM_FOO, "MY_ENUM_FOO", "foo" },
    { MY_ENUM_BAR, "MY_ENUM_BAR", "bar" },
    { 0, NULL, NULL }
  };  
   
  g_enum_complete_type_info (type, info, values);  
}
| g_enum_type: | the type identifier of the type being completed | 
| info: | the GTypeInfo struct to be filled in | 
| const_values: | An array of GEnumValue structs for the possible enumeration values. The array is terminated by a struct with all members being 0. | 
void g_flags_complete_type_info (GType g_flags_type, GTypeInfo *info, const GFlagsValue *const_values);
This function is meant to be called from the complete_type_info() function 
of a GTypePlugin implementation, see the example for 
g_enumeration_complete_type_info() above.
| g_flags_type: | the type identifier of the type being completed | 
| info: | the GTypeInfo struct to be filled in | 
| const_values: | An array of GFlagsValue structs for the possible enumeration values. The array is terminated by a struct with all members being 0. |