ComponentMacro.hx

package org.devboy.hxTask;

import neko.Lib;
import haxe.macro.Context;
import haxe.macro.Expr;
import haxe.macro.Type;

class ComponentMacro
{
	private static var idCount = 0;

	@:macro
	public static function build(): Array<Field>
	{
		var pos = haxe.macro.Context.currentPos();
        var fields = haxe.macro.Context.getBuildFields();
        Lib.println( fields );
       	var tint = TPath({ pack : [], name : "Int", params : [], sub : null });
        	fields.push( { name : "id", doc : null, meta : [], access : [APublic], kind : FVar(tint, null), pos : pos });
        	fields.push( { name : "ID", doc : null, meta : [], access : [AStatic], kind : FVar(tint, null), pos : pos });
        return fields;
	}	
}

Main.hx

package org.devboy.hxTask;

import neko.Lib;
import haxe.macro.Expr;
import haxe.macro.Context;
import org.devboy.hxTask.ComponentMacro;

class Main
{
	public static function main()
	{
		Lib.println( ComponentA.ID );
	}
}

@:autoBuild( org.devboy.hxTask.ComponentMacro.build() )
interface Component 
{
	var id:Int;
}

class ComponentA implements Component
{
}