GeezerVison

I don't think this change is necessary... unless I'm missing something.

We're using the Tag type to determine the character type being placed in the array definition. If anything, I suspect you want to lift the trait to determine what the buffer type should be for a given tag.

My thought was that I didn't want to redefine the buffer_type in the parser, which is just a helper class. The actual buffer type is defined in the class utilizing the parser, and then just forwarded. IMHO it was redundancy introduced by mistake which enforced redefinition of exactly the same buffer type in a helper class.

True, but not in the way it's designed to use traits to dispatch on the tag. Arguably the problem is that we're hard-coding the type of the buffer instead of using the tag-based dispatch we've been using everywhere. Because this is currently an implementation detail, I think the way you've done it is fine -- but that we might want to think about the wider design of this, so that it can be applied more systematically.

At this point, since the tests pass I'm willing to merge this as-is, but something worth thinking about in the future to clean this up better.