Is there anyway to make opApply @nogc?

[Gary Willoughby via Digitalmars-d-learn]

Is there any way to make opApply @nogc? or provide the same 
foreach functionality without implementing a range interface?

I want to iterate over a piece of memory using a pointer. I 
thought about using opSlice but that doesn't provide information 
for an index in a foreach loop.

auto opSlice()
{
    return this._pointer[0 .. size];
}

Anyone got any ideas?