why no ++?

[plakal at nospam-cs.wisc.edu]

Alex Martelli <aleax at aleax.it> wrote:
>     y.a = b,c,d = x.e = wower()
> How would you like to rewrite _this_?-)  There is *NO* rewrite
> that ensures constant semantics except by introducing _another_
> temporary variable -- *yecch*!-)

	Is there a case where the following rewrite
	would not be valid (in versions of Python
	that don't have get/set-operator support)?
	
	      y.a = wower()
              b,c,d = y.a
              x.e = y.a

	Manoj