gistfile1.hx

class AA
{
	public var x:Float;
	public var y:Float;
	
	inline public function new(x:Float, y:Float) 
	{ 
		this.x = x;
		this.y = y;
	}
}
abstract BB(AA)
{
	public var x(get, set):Float;
	public var y(get, set):Float;
	
	
	inline public function get_x():Float return this.x;
	inline public function get_y():Float return this.y;
	
	inline public function set_x(v:Float):Float return this.x = v;
	inline public function set_y(v:Float):Float return this.y = v;
	
	public inline function new(x:Float = 0, y:Float = 0)
	{
		this = new AA(x, y);
	}
	
	@:commutative @:op(A*B) inline public static function opMulSF(a:BB, s:Float):BB
	{
		return new BB(a.x * s, a.y * s);
	}
}


class Main
{

	static function main()
	{
		var a = new BB(10, 20);
		
		var t1 = 1.0;
		var t2 = 2.0;
		
		// !!! fails here
		var fail = a * (t1 + t2); 
		
		// ok here
		var cacheSum = (t1 + t2);
		var ok = a * cacheSum; 
	}
}

gistfile2.js

var Main = function() { };
Main.main = function() {
	var a_x = 10;
	var a_y = 20;
	var t1 = 1.0;
	var t2 = 2.0;
	var fail;
	var s = t1 + t2;
	fail = new AA(a_x * s,a_y * s);
	var cacheSum = t1 + t2;
	var ok_x = a_x * cacheSum;
	var ok_y = a_y * cacheSum;
};