Re: 7 logical-xor implementations in source tree

[Stefan Monnier]

> It defines xor using defsubst instead of define-inline, so that it can
> be included in subr.el.

Great, thanks.

> Would defun be preferred instead?

No proeference here.

> It also includes Mattias' equiv suggestion.

Not convinced about this one:
- The name is too much like "equal/eq/eql": we need something much
  more explicit to avoid adding to the already existing confusion.
  I'd go with something like `bool-equal`.
- The fact that it's not a function is a definite downside.
- There's no use for it, currently.  If we can't find any use for it,
  I'm not sure it deserves to be in subr.el.
  Actual/potential uses of it might also help figure out if having it as
  a function would be beneficial/useful and whether the detail about
  which non-nil value is returned is important and whether supporting
  more than 2 args is important.


        Stefan