linux-packaging-mono/mcs/tests/test-687.cs

using System;

struct XUnit
{
	public XUnit(double point)
	{
		this.Point = point;
	}

	double Point;

	public static implicit operator XUnit(double value)
	{
		XUnit unit;
		unit.Point = value;
		return unit;
	}

	public static implicit operator double(XUnit value)
	{
		return value.Point;
	}
}

struct Unit
{
	public Unit(double point)
	{
		this.Point = point;
	}

	double Point;

	public static implicit operator Unit(double value)
	{
		Unit unit;
		unit.Point = value;
		return unit;
	}

	public static implicit operator double(Unit value)
	{
		return value.Point;
	}
}

class Test
{
	public static int Main()
	{
		XUnit xunit = new XUnit();
		Unit unit = new Unit();
		Unit uu = unit + xunit;
		unit += xunit;
		return 0;
	}
}