Thread: scoped enums only available with -std=c++0x or std=gnu++0x

Hi - First post, so please be gentle with me if I breached any rules or anything... Thanks.

I am reading C++ Without Fear (second edition). Near the end of chapter 10 I am tasked with updating a "rock Paper scissors" game.

Now, I understand the code and I am pretty sure that I can complete the tasks set, however, when I bring the example program into Dev-C++ OR Code:Blocks I am unable to compile it. Here's the first part of the code - The GCC compiler stops at the "enum" line:

Code:

#include <iostream>
#include <string>
#include <ctime>
using namespace std;


enum class Choice { rock, paper, scissors };

Dev-C++ says:
expected identifier before "class".

This is very frustrating as this is the IDE recommended by the book... and the compiler came bundled with it.

As a test I tried Codeblocks and codeblocks tells me:
scoped enums only available with -std=c++0x or std=gnu++0x

Am I right in thinking that I have out of date compiler that doesn't understand C++0x instructions? and if so, can someone point me in the right direction to get one please?

Thanks in advance,

B.

(I hope this is in the right section of the forum, if not please accept my apologies.)

Thanks for your help, I ticked the box in the global compiler settings in codeblocks that said:


Have G++ Follow the coming C++ ISO C++ language standard [-std=c++0x]

Is that all I needed to do?

The reason I ask is because I am now stuck at the line of code that declares using namespace choice;

Code:

#include <iostream>
#include <string>
#include <ctime>
using namespace std;


enum class Choice { rock, paper, scissors };
using namespace Choice;


Choice player_choice;     // Holds user's move
Choice computer_choice;   // Holds computer move

The errors (from codeblocks) are:


'choice' is not a namespace-name
and
expected namespace-name before ";" token

Surely this is not a C++0x problem... This is very frustrating, (I'm a bit angry with the author over this, how can anyone learn from code that doesn't work?)

Anyway,like I said, thanks V much, I'm grateful for your help. The next chapter in the book is about classes so perhaps I will learn a bit more and come back to this one.

Well.. Choice isn't a namespace...It is just a scope for the enum values.
You'd still have to put Choice::rock ..etc when using the values.

Thanks for taking the time to help me,

Quote from Book:

C++0x supports both weak and strong enum (enumerated types). Use of enum
class (see the following example) creates a strongly typed set of enumerated values
in which a separate namespace is created and values cannot be assigned to or
from another integer type without a cast.

Code:

enum class type_name { symbols };

When using this version (strongly typed), remember the symbols listed are in a
separate namespace and have to be referred to with class scope, unless you have a
using namespace statement. For example:

Code:

enum class Choice { rock, paper, scissors };


Choice player = Choice::rock;


using namespace Choice;
Choice comp = scissors; // Now this is ok.

So, is the book in error? - it would be a shame as this book is recommended on this site as the first step on the path from beginner to expert. I'm hoping it's another setting in my compiler that I need to set...