PEP 218 Re: ANN: set-0.1 module available

[Ian Bicking]

On Mon, 2002-05-20 at 20:59, Huaiyu Zhu wrote:
> id(a) === id(b) implies a === b
> a === b implies a==b
> a === b implies hash(a) === hash(b)
> a == b, a is const, b is const implies a === b

This is kind of like in Scheme, which has four equal functions -- eq?,
eqv?, equal? and =.  eq? is the same as "is".  equal? and = are like
"==" (= in Scheme is just for numbers).  You are proposing the middle
ground of eqv?  (stands for equivalent)

R5RS probably clarifies the semantics for eqv? in Scheme, it might be
useful to consider.

  Ian