[Python-Dev] A Horrible Inconsistency

[Raymond Hettinger]

Fredrik Lundh wrote:

> >>> -1 * (1, 2, 3)
>()
> >>> -(1, 2, 3)
>Traceback (most recent call last):
>   File "<stdin>", line 1, in <module>
>TypeError: bad operand type for unary -
>
>We Really Need To Fix This!
>  
>

The second one doesn't bug me.  Unary minus on a sequence is meaningless.

The first is a bit odd.  When using the * operator for sequence 
repetition, I don't expect it to have the same commutative property as 
multiplication.  IOW, "seq * n" makes sense but "n * seq" is a bit 
weird.  Also, I'm not clear on the rationale for transforming negative 
repetition counts to zero instead of raising an exception.  OTOH, 
neither of these has EVER been an issue for me or anyone I know.


Raymond