Re: UDAs on enum members

[Walter Bright via Digitalmars-d]

On 7/13/2016 4:57 AM, Tomer Filiba wrote:
It would be really nice if I could put UDAs on enum members as well, e.g.,
enum MyEnum {
    @("SOM") SomeMember,
    @("ANO") AnotherMemberWithAVeryLongName,
}

Not a bad idea. It's been asked for before.


And while we're on the subject, why can't enums have methods? At the risk of
sounding as if I like Java (I don't :) ), it's a really nice language feature.
Back to our example:

enum MyEnum {
    @("SOM") SomeMember,
    @("ANO") AnotherMemberWithAVeryLongName;

    string dump() {
        ...  // `this` is a value, not a ref here
    }
    static MyEnum load(string name) {
        ...
    }
}

Basically just allow a semicolon at the end of the members, after which methods
could appear. Adding members or whatever else Java has is an overkill -- just
use a struct for that. But instead of lots of dumpMyEnum(MyEnum
e)/loadMyEnum(string s) pairs, you could write myMember.dump()/MyEnum.load(s)


struct MyEnum {
    @("SOM") enum SomeMember = 0;
    @("ANO") enum AnotherMemberWithAVeryLongName = 1;

    string dump() {
        ...  // `this` is a value, not a ref here
    }
    static MyEnum load(string name) {
        ...
    }
}

Not as nice, but gets the job done. But adding a new aggregate type comes with a 
lot of baggage. I'm not convinced the complexity is worth the benefit, which 
seems minor.