Andy Wingo <wi...@pobox.com> writes: > On Wed 20 Jun 2012 15:41, Noah Lavine <noah.b.lav...@gmail.com> writes: > >> I believe David's claim is that Guile should guarantee that a variable >> is eq? to itself, even though the standard doesn't. > > We could guarantee this, but it would prevent a number of interesting > and permissible optimizations, for questionable semantic value.
Name one. > You should not consider variables as having identity, only values. > Numbers do not have identity, so Guile can do with them as it pleases. Let's throw an error whenever using eq? on a number or running memq on a list containing a number. That would be interesting and apparently permissible behavior. I have my doubts that users will be impressed favorably. -- David Kastrup
