exception message output problem

[Bruno Desthuilliers]

Lie a écrit :
> On Dec 22, 6:18 am, Bruno Desthuilliers
> <bdesth.quelquech... at free.quelquepart.fr> wrote:
> 
>>Lie a écrit :
>>(snip)
>>
>>
>>># Python have an odd (read: broken) singleton implementation
>>># single member tuple must have a comma behind it
>>
>>You may call it weird or even a wart if you want, but given that what
>>makes the tuple is the comma - not the parens[1] -, it is _not_ broken.
>>
>>[1] with the exception of the empty tuple.
> 
> 
> I also realized that you don't need to use parens to make tuple, it's
> rather my habit to always use parens in making a tuple

FWIW, almost anybody does so except in a couple cases (mostly related to 
tuple unpacking). First because it's more readable, and also because - 
as you noticed - there are cases where you need the parens to force 
evaluation order.

> PS: My wording on broken doesn't actually means broken so it won't
> work, but rather broken syntactically, making the syntax inconsistent,
> funny, illogical, etc. One could argue though that the trailing comma
> is a formalized workaround.

The problem is that there are not so many "grouping" characters 
available, and that parens end up being used for too many things: 
function call operator, function arguments definitions, evaluation order 
(grouping) and the empty tuple (and now generator expressions). I guess 
this would make it impractical for the parser to have to distinguish 
between grouping and literal tuples. So while I agree it's a bit weird, 
it's not illogical - once you get the logic !-)