[swift-evolution] protocol-oriented integers (take 2)

[David Sweeris]

Sent from my iPhone
> On Jan 15, 2017, at 18:02, Xiaodi Wu <xiaodi.wu at gmail.com> wrote:
> 
> "Mathematically correct" integers behave just like Int in that there is not a multiplicative inverse. What we're trying to do here is to determine how much of what we know about mathematics is usefully modeled in the standard library. The answer is not zero, because there is more than just counting that people do with integers.

It's an interesting problem... When I was in school, "integer" division "returned" a "quotient and remainder", a "fraction" (which, occasionally, could be simplified to just an integer), or a "real". We never talked about division in the context of "(Int, Int) -> Int", though. OTOH, I never took any math classes past Differential Equations or Linear Algebra, either... I'm aware of areas of math where you formally restrict yourself to the kind of "(Int, Int) -> Int" operations we're doing here, but I don't really know much about it. Is division even well-defined in that context?

- Dave Sweeris
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-evolution/attachments/20170115/a3229142/attachment.html>