Re: Interesting list Validity (True/False)

On May 12, 8:10?pm, Carsten Haese <cars...@xxxxxxxxxxx> wrote:
On Sat, 2007-05-12 at 17:55 -0700, mensana...@xxxxxxx wrote:
On May 12, 12:56?pm, Carsten Haese <cars...@xxxxxxxxxxx> wrote:
On Fri, 2007-05-11 at 14:26 -0700, mensana...@xxxxxxx wrote:
if arg==True:

tests the type property (whether a list is a boolean).

That sounds nonsensical and incorrect. Please explain what you mean.

<quote>
Sec 2.2.3:
Objects of different types, except different numeric types and
different string types, never compare equal;
</quote>

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'>


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>

None of these four examples are "equal" to any other.

a = 1
b = (1,)
c = [1]
d = gmpy.mpz(1)

type(a)
<type 'int'>
type(b)
<type 'tuple'>
type(c)
<type 'list'>
type(d)
<type 'mpz'>
a==b
False
b==c
False
a==d
True

And yet a==d returns True. So why doesn't b==c
also return True, they both have a 1 at index position 0?

x = [1]
y = [1]
x==y
True



--
Carsten Haesehttp://informixdb.sourceforge.net


.

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