why () is () and [] is [] work in other way?

[Terry Reedy]

On 4/23/2012 4:37 PM, Devin Jeanpierre wrote:

> However, you appear to be trying to shift the goalposts. Either "1 is
> 1" is always True, or always False, or sometimes one or the other. If
> I'm mistaken and it so happens that numeric constants are guaranteed
> somewhere to always be cached, then replace it with the empty tuple.
> It is a fact that the result is not always the same,

The result is always the current truth of the matter.

> and you're trying to dodge around that. :/

In a previous post you chided Stephen for an ad hominem comment. Above 
you make two. Both are false. I am insisting that Python's 'is' should 
be judged as what it is, which is a non-mathematical introspection 
function. And I am hardly dodging around something I have understood and 
been telling and warning people about on comp.lang.python and thisn list 
for 15 years. That is a nasty lie.

>> It is wrong to interpret the Python expression '1 is 1' as a mathematical
>> expression. It simply is not such. Trying to do so only leads to confusion,
>> as this thread show.
>
> Of course it's a mathematical expression.

Bollocks. It is a question about a non-mathematical* fact of 'the 
world', which is a Python computing session.
* As I understand the adjective 'mathematical'.

Consider the expression 'Bob is Robert'. If it means "The string 'Bob' 
is the string 'Robert'" then is would be a mathematical expression of 
string theory and the answer would be False. If it means "The person 
connected with the name 'Bob' at this time in the currect context is the 
same person connected with 'Robert'", then it is not a mathematical 
question but is contingent# on the facts of the world.

# Contingency is not ambiguity.

Anyway, I think I am done with this thread.

-- 
Terry Jan Reedy