On Mon, Jul 2, 2018 at 11:50 PM, Chris Barker <chris.barker@noaa.gov> wrote:
- keep the key function optional parameter.
- add a value function optional parameter. -- it really makes any case where you don't want to store the whole item a lot easier.

- Have the default key function be itemgetter(0) and the default value function be itemgetter(1) (or some similar way to implement default support for processing an iterable of (key, value) pairs.

Having no value function and an equality default for the key function may be "common", but it's also pretty much useless -- why have a useless default?

Thinking this through now I do see that having key and value default to to the pair method means that if you specify  key function, you will probably have to specify a value function as well -- so maybe that's not ideal.

OK, I prototyped a class solution that defaults to key, value pairs, but you can specify a key and/or value function. and with convoluted logic, if you specify just a key, then the value defaults to the entire item. So folks will pretty much get what they expect.

I think it's actually pretty slick -- best of both worlds?

Code here:




Christopher Barker, Ph.D.

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