#include <map>
#include <vector>
#include <string>

namespace json {

class value;

typedef std::vector<value> array;
typedef std::map<std::string, value> object;
typedef std::string string;

enum class type
{
    null,
    boolean,
    integer,
    number,
    string,
    object,
    array
};

class value
{
public:
    type type;
    union
    {
        int integer;
        double number;
        bool boolean;
        string* string;
        array* array;
    };
};

}

Ist folgendes gueltiges C++11?

#include <map>
#include <vector>
#include <string>

namespace json {

class value;

typedef std::vector<value> array;
typedef std::map<std::string, value> object;
typedef std::string string;

enum class type
{
    null,
    boolean,
    integer,
    number,
    string,
    object,
    array
};

class value
{
public:
    type type;
    union
    {
        int integer;
        double number;
        bool boolean;
        string* string;
        array* array;
    };
};

}

nein.

n3337 schrieb:

3.3.7 Class scope [basic.scope.class]
The following rules describe the scope of names declared in classes.

1. The potential scope of a name declared in a class consists not only of the declarative region following
   the name’s point of declaration, but also of all function bodies, brace-or-equal-initializers of non-static
   data members, and default arguments in that class (including such things in nested classes).
2. A name N used in a class S shall refer to the same declaration in its context and when re-evaluated in
   the completed scope of S. No diagnostic is required for a violation of this rule.
3. If reordering member declarations in a class yields an alternate valid program under (1) and (2), the
   program is ill-formed, no diagnostic is required.
4. A name declared within a member function hides a declaration of the same name whose scope extends
   to or past the end of the member function’s class.
   ...

type type; 
bool boolean; 
string* string; 
array* array;

Eigentlich klar ... aber was ist mit dem ersten Teil?

typedef std::vector<value> array; 
typedef std::map<std::string, value> object; 
typedef std::string string; 

enum class type 
{
    ...
    string, 
    object, 
    array 
};

Es wird zumindest vom gcc 4.7.1 geschluckt.

class value
  {
  public:
    json::type type;
    union
    {
      int integer;
      double number;
      bool boolean;
      json::string* string;
      json::array* array;
    };
  };

Damit dürfte doch im Scope von value alles eindeutig sein.

was ist mit dem ersten Teil?

typedef std::vector<value> array; 
typedef std::map<std::string, value> object; 
typedef std::string string; 
  
enum class type 
{
    ...
    string, 
    object, 
    array 
};

Es wird zumindest vom gcc 4.7.1 geschluckt.

Verschiedene Scopes, also kein Problem.

Dank auch dir camper.