How can I create nested enum like structures?

instead of Enum.X_Y I would like to access like Enum.X.Y

Yet I want it to behave exactly as an enum.  I just want to not use _ as .'s are better as they express more clearly what I want.

On Wednesday, 24 August 2016 at 23:04:25 UTC, Illuminati wrote:
> How can I create nested enum like structures?
>
> instead of Enum.X_Y I would like to access like Enum.X.Y
>
> Yet I want it to behave exactly as an enum.  I just want to not use _ as .'s are better as they express more clearly what I want.

struct MyEnum {
    enum X { Y = 10, Z = 20 }
}

void main() {
    import std.stdio;
    int y = MyEnum.X.Y;
    writeln(y);
}

And if you need more levels:

struct MyEnum {

    static struct AnotherEnum {

        enum X { Y = 10, Z = 20 }

    }

}

void main() {
    import std.stdio;
    int y = MyEnum.AnotherEnum.X.Y;
    writeln(y);
}

Dne 25.8.2016 v 03:37 Mike Parker via Digitalmars-d-learn napsal(a):
> On Wednesday, 24 August 2016 at 23:04:25 UTC, Illuminati wrote:
>> How can I create nested enum like structures?
>>
>> instead of Enum.X_Y I would like to access like Enum.X.Y
>>
>> Yet I want it to behave exactly as an enum.  I just want to not use _ as .'s are better as they express more clearly what I want.
>
> struct MyEnum {
>     enum X { Y = 10, Z = 20 }
> }
>
> void main() {
>     import std.stdio;
>     int y = MyEnum.X.Y;
>     writeln(y);
> }

On Wednesday, 24 August 2016 at 23:04:25 UTC, Illuminati wrote:
>

Well those other answers aren't wrong, but I envisioned that you'd have multiple categories within your sub-enums and whatnot, so you'd need something more like this:

struct A {
	enum X {
		one,
		two,
		three,
	};
	enum Y {
		four = X.max + 1,
		five,
		six,
	};
	enum Z {
		seven = Y.max + 1,
		eight,
		nine,
	};
};

Continuing each enumeration from the end of the previous ensures you won't get any fields with the same values.

Btw, tehre is no need for extra semicolon (`;`) after enum and struct definition


Dne 25.8.2016 v 12:23 Cauterite via Digitalmars-d-learn napsal(a):
> On Wednesday, 24 August 2016 at 23:04:25 UTC, Illuminati wrote:
>>
>
> Well those other answers aren't wrong, but I envisioned that you'd have multiple categories within your sub-enums and whatnot, so you'd need something more like this:
>
> struct A {
>     enum X {
>         one,
>         two,
>         three,
>     };
>     enum Y {
>         four = X.max + 1,
>         five,
>         six,
>     };
>     enum Z {
>         seven = Y.max + 1,
>         eight,
>         nine,
>     };
> };
>
> Continuing each enumeration from the end of the previous ensures you won't get any fields with the same values.

On Thursday, 25 August 2016 at 10:36:21 UTC, Daniel Kozak wrote:
> Btw, tehre is no need for extra semicolon (`;`) after enum and struct definition

Thanks. This forum insists on reminding me every time I write code here.

On Thursday, 25 August 2016 at 11:09:43 UTC, Cauterite wrote:
> On Thursday, 25 August 2016 at 10:36:21 UTC, Daniel Kozak wrote:
>> Btw, tehre is no need for extra semicolon (`;`) after enum and struct definition
>
> Thanks. This forum insists on reminding me every time I write code here.

Warning about this is now an enhancement request: https://issues.dlang.org/show_bug.cgi?id=16430

On Thursday, 25 August 2016 at 01:37:05 UTC, Mike Parker wrote:
> On Wednesday, 24 August 2016 at 23:04:25 UTC, Illuminati wrote:
>> How can I create nested enum like structures?
>>
>> instead of Enum.X_Y I would like to access like Enum.X.Y
>>
>> Yet I want it to behave exactly as an enum.  I just want to not use _ as .'s are better as they express more clearly what I want.
>
> struct MyEnum {
>     enum X { Y = 10, Z = 20 }
> }
>
> void main() {
>     import std.stdio;
>     int y = MyEnum.X.Y;
>     writeln(y);
> }

Thanks. I should have thought of that.