Is there a way of getting the names of all subclasses

Question

I want to get the names of all subclasses of a base class. From that I want to @:build an enum where every entry is the name of a class. Is this possible?

Answer 1

Here is the code. The order of macro executions is undefined, as specified in documentation.

[AutoBuildingMacro.hx]

import haxe.macro.Context;
import haxe.macro.Expr;

final mapofnames = new Map<String,Array<String>>();

class AutoBuildingMacro {
  public static macro function fromBaseClass(base):Array<Field> {
    var parent = haxe.macro.ExprTools.toString(base);
    var names = mapofnames[parent];
    if ( names == null ) {
      names = new Array<String>();
      mapofnames[parent] = names;
    }
    names.push(Context.getLocalClass().toString());
    trace(mapofnames);
    return null;
  }
}

[Main.hx]

import AutoBuildingMacro;

class Main {
  static public function main() {}
}

@:autoBuild(AutoBuildingMacro.fromBaseClass(Parent))
class Parent {
}

class Child1 extends Parent {
}

class Child2 extends Parent {
}

class Child3 extends Child2 {
}

Output:

AutoBuildingMacro.hx:15: {Parent => [Child2]}

AutoBuildingMacro.hx:15: {Parent => [Child2,Child3]}

AutoBuildingMacro.hx:15: {Parent => [Child2,Child3,Child1]}