StdlibIntKit

[oscbyspro]

I want to test some ordinary Swift.BinaryInteger stuff. A StdlibInt<T> type would enable it. Swift.BinaryInteger is approximately a trapping Ultimathnum.FiniteInteger, so it should be simple to implement. The only thing I haven't covered yet is binary floating-point conversions, which I'll get to eventually.

[oscbyspro]

I might need two types since Swift does not have a notion of infinity. Alternatively, I could settle on a signed big integer type that wraps InfiniInt<IX>. That would cover most things I have in mind. Hm.

[oscbyspro]

I've settled on a big, signed, StdlibInt. It uses TextInt too because Swift does not have an arbitrary decoding method.