Duncan Booth wrote: > Boris Borcic <[EMAIL PROTECTED]> wrote: >> Arnaud Delobelle wrote: >>> Whereas when "3.0*1.0 is 3.0" is evaluated, *two* different float >>> objects are put on the stack and compared (LOAD_CONST 3 / LOAD_CONST >>> 1 / COMPARE_OP 8). Therefore the result is False. >> Looks good, but doesn't pass the sanity check ;) Consider >> >>>>> def f(): >> return 3 is 3, 3*1 is 3 >> >>>>> import dis >>>>> dis.dis(f) >> 2 0 LOAD_CONST 1 (3) >> 3 LOAD_CONST 1 (3) >> 6 COMPARE_OP 8 (is) >> 9 LOAD_CONST 3 (3) >> 12 LOAD_CONST 1 (3) >> 15 COMPARE_OP 8 (is) >> 18 BUILD_TUPLE 2 >> 21 RETURN_VALUE >>>>> f() >> (True, True) >> > > s/different/possibly different depending on implementation details/
"0 substitutions made", but whatever s/on implementation details/on further implementations details/ > Arnaud's point remains valid: in the first comparison you can see that the > same object is used, in the second case all bets are off. Sure, but the issue was to explain the strangeness that (3.0 is 3.0)!=(3.0*1.0 is 3.0) and I just pointed out - without drawing any conclusion - that a structurally identical explanation would "explain" the contrafactual (3 is 3)!=(3*1 is 3). Best, BB -- http://mail.python.org/mailman/listinfo/python-list
