On 19 May 2016 at 08:53, Guido van Rossum firstname.lastname@example.org wrote:
The one thing that Python doesn't have (and mypy doesn't add) would be a match statement. The design of a Pythonic match statement would be an interesting exercise; perhaps we should see how far we can get with that for Python 3.7.
If it's syntactic sugar for a particular variety of if/elif/else statement, I think that may be feasible, but you'd presumably want to avoid the "Can we precompute a lookup table?" quagmire that doomed PEP 3103's switch statement.
That said, for the pre-computed lookup table case, whatever signature deconstruction design you came up with for a match statement might also be usable as the basis for a functools.multidispatch() decorator design.