C#3.0 and lambdas

[Steven Bethard]

Steven D'Aprano wrote:
> Consider this:
> 
> def func(some_tuple):
> 
> How many items should you pass in the tuple? If it takes variable
> arguments, then that works, but if you always expect a fixed number, then
> 
> def func((x, y))
> 
> is more explicit.
> 
> The only problem I have is that once you unroll the tuple like that, it is
> hardly necessary to pass the argument as a tuple. Why not just pass x and
> y as two arguments?
> 
> def func(x, y)

I generally agree with this (and follow the same guideline in my own 
APIs), but sometimes you don't have this option.  If I have a class that 
I'd like to support an indexing operation like:

    obj[x, y]

then the natural __getitem__ signature will look like:

    def __getitem__(self, (x, y)):
        ...

STeVe