Re: Can I count the of enum's fields at compile time?

[Ali Çehreli via Digitalmars-d-learn]

On 11/22/2017 05:21 PM, Marc wrote:

On Thursday, 23 November 2017 at 01:04:29 UTC, Jonathan M Davis wrote:

On Thursday, November 23, 2017 00:58:21 Marc via Digitalmars-d-learn wrote:

for example:

enum A { a = -10, b = -11, c = -12, d = -13, e = -34}

enum int countOfA = coutOfFields(A); // 5 fields

import std.traits;

enum countOfA = EnumMembers!A.length;

- Jonathna M Davis

This sounds more readable. I was going to write a "function extension" to enum but I think it isn't really needed. Thank you too.

As an eponymous template:

enum One { a }
enum Three { a, b, c }

import std.range : EnumMembers;
enum countOf(E) = EnumMembers!E.length;

unittest {
    static assert(countOf!One == 1);
    static assert(countOf!Three == 3);
}

void main() {
}

Ali