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[nitz]

nitz

Using a class encapsulated enum without fully qu...

Say I have a class such as:

Code: [Select]

typedef class _myClass
{
public:
enum Directions { UP = 0, DOWN, LEFT, RIGHT };
}MyClass;

When trying to get at one of the directions, I'd have to get at it by:

MyClass::UP

Is there a way I can scope things in, so that I can have access to it by just using UP?

Thoughts?

http://thegroupofthey.com/

• 

[Windy]

Windy

Re: Using a class encapsulated enum without full...

#define UP MyClass::UP

?

[MG-Zero]

MG-Zero

Re: Using a class encapsulated enum without full...

All you have to do is type in UP so long as the variable your assigning it to is an int.

int x = UP;

should work just fine, it does when I do it.

i love big weenies and i cannot lie

[nitz]

nitz

Re: Using a class encapsulated enum without full...

#define UP MyClass::UP

?

This would work, but not quite the solution I'm going for. I'd rather have something done by the compiler, rather than the preprocessor. Thanks though!

All you have to do is type in UP so long as the variable your assigning it to is an int.

int x = UP;

should work just fine, it does when I do it.

Maybe it's my compiler, but it sure doesn't work for me.
Screenshot:

http://thegroupofthey.com/

• 

[Trask]

Trask

Re: Using a class encapsulated enum without full...

It's because you're trying to use the enum that you declared in the class, outside of the class. I personally, would define my enum globally in this case.

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- Trask

[MG-Zero]

MG-Zero

Re: Using a class encapsulated enum without full...

Quote from: MG-Zero on Today at 01:09:15 PM
All you have to do is type in UP so long as the variable your assigning it to is an int.

int x = UP;

should work just fine, it does when I do it.

Maybe it's my compiler, but it sure doesn't work for me.
Screenshot:

sorry I made an error >.<

I forgot to mention you'll have to make an instance of the enumeration, and since it's in the class you'll have to do the same for that to and then use the UP value for that enumeration.  Do what Trask said and make the enum global, that way you won't need a class instance.  So you can just do...

Code: [Select]

Direction Direction;

int x = Direction.UP;


i love big weenies and i cannot lie

[therabidwombat]

therabidwombat

Re: Using a class encapsulated enum without full...

@nitz: I think to do what you're trying to do in the screenshot post, you'd have to access the enum through teh scope resolution operator (for example, _myClass::UP), and even then, the enum might have to be static, I'm not too sure about that though [I've been using C# for a while and tiny details like that I have forgotten]

• 

[nitz]

nitz

Re: Using a class encapsulated enum without full...

@nitz: I think to do what you're trying to do in the screenshot post, you'd have to access the enum through teh scope resolution operator (for example, _myClass::UP), and even then, the enum might have to be static, I'm not too sure about that though [I've been using C# for a while and tiny details like that I have forgotten]

That was the point of my original post: I want to get at it without using the SRO. It doesn't have to be static, though.

It's because you're trying to use the enum that you declared in the class, outside of the class. I personally, would define my enum globally in this case.

That was the point. I want the enum to be in the class. The trick is, I want to get access to it as if it were in a namespace.

Quote from: MG-Zero on Today at 01:09:15 PM
All you have to do is type in UP so long as the variable your assigning it to is an int.

int x = UP;

should work just fine, it does when I do it.

Maybe it's my compiler, but it sure doesn't work for me.
Screenshot:

sorry I made an error >.<

I forgot to mention you'll have to make an instance of the enumeration, and since it's in the class you'll have to do the same for that to and then use the UP value for that enumeration.  Do what Trask said and make the enum global, that way you won't need a class instance.  So you can just do...

Code: [Select]

Direction Direction;

int x = Direction.UP;


That doesn't work. That may work in C#, but the '.' operator is the direct membership operator; and 'UP' is not a member of 'Directions'. As well, with the enumeration in global scope, you don't need to declare an instance of the enumeration, there already is one - in global scope.

http://thegroupofthey.com/

• 

[MG-Zero]

MG-Zero

Re: Using a class encapsulated enum without full...

yea, i was a bit off.  I just checked my textbook, although you still have to create an instance of the enum, you dont need the . operator.  And i'm not talking about C#, i'm talking about C++.

edit: from my book:

Code: [Select]

int main()
{
enum days = {Sunday, monday, tuesday, wednesday, thursday, friday, saturday };

days today;

today = monday;

//rest of code for outputting the day here, which is useless for this example..
}

anyway, yea, there it is used properly.

i love big weenies and i cannot lie

[nitz]

nitz

Re: Using a class encapsulated enum without full...

yea, i was a bit off.  I just checked my textbook, although you still have to create an instance of the enum, you dont need the . operator.  And i'm not talking about C#, i'm talking about C++.

edit: from my book:

Code: [Select]

int main()
{
enum days = {Sunday, monday, tuesday, wednesday, thursday, friday, saturday };

days today;

today = monday;

//rest of code for outputting the day here, which is useless for this example..
}

anyway, yea, there it is used properly.

Yeah, but that's still declaring the enum inside of that function. I'm trying to get at it while leaving it in the class declaration.

http://thegroupofthey.com/

• 

[MG-Zero]

MG-Zero

Re: Using a class encapsulated enum without full...

hmm...how about something like..

Code: [Select]

class classname
{
enum enumname
{
black,
red,
white
};

};

classname object;

object.enumname enuminstnace;


?  Just a guess, i've never worked with an enum this way before.

i love big weenies and i cannot lie