On May 13, 8:57?am, Carsten Haese <[EMAIL PROTECTED]> wrote: > On Sat, 2007-05-12 at 18:43 -0700, [EMAIL PROTECTED] wrote: > > > That doesn't explain what you mean. How does "if arg==True" test whether > > > "a list is a boolean"? > > > >>> type(sys.argv) > > <type 'list'> > > >>> type(True) > > <type 'bool'> > > All right, so what you meant was "Assuming that arg is a list, 'if > arg==True' will always fail because lists never compare equal to any > boolean." > > > Actually, it's this statement that's non-sensical. > > > <quote> > > "if arg==True" tests whether the object known as arg is equal to the > > object known as True. > > </quote> > > > [snip examples of "surprising" equality tests...] > > The statement I made is simply the meaning of "if arg==True" by > definition, so I don't see how it can be nonsensical.
Because you didn't allow for exceptions, which are prominently pointed out in the Python docs. > > The problem is that you consider equality tests in Python to be > nonsensical because they don't fit with your opinion of what equality > should mean. No, it has nothing to do with what it means. 1, [1], (1,) and mpz(1) are all different types and all mathmatically the same. Yet 1 and mpz(1) compare equal but (1,) and [1] do not. The later fails due to type mis-match, the former does not despite type mis-match due to the fact they are the same mathematically. I'm not saying the situation is wrong, what I'm saying is that somone who doesn't understand why arg==True is failing should be told ALL the rules, not just the easy ones. > > Regards, > > -- > Carsten Haesehttp://informixdb.sourceforge.net -- http://mail.python.org/mailman/listinfo/python-list
