Miscellaneous 0.9.0 stuff

[oscbyspro]

I'll use this thread to document various minor changes.

[oscbyspro]

I'll disambiguate the following BinaryInteger.init(load:) cases:

let ix = IX.random()
let ux = UX.random()

IX(load: InfiniInt<IX>(load: ix))
IX(load: InfiniInt<UX>(load: ix))
UX(load: InfiniInt<IX>(load: ux))
UX(load: InfiniInt<UX>(load: ux))

IX(load: DoubleInt<IX>(load: ix))
IX(load: DoubleInt<UX>(load: ix))
UX(load: DoubleInt<IX>(load: ux))
UX(load: DoubleInt<UX>(load: ux))

[oscbyspro]

I'll rename T.Failure as T.Error. I see it as Value & Error vs Success & Failure and I want to be consistent about it.

[oscbyspro]

Seems silly, but going from A to B improves decoding performance ~2x (for small integers).

This is in a TextInt extension:

// MARK: A (slow)

try description.withUTF8(self.decode)

// MARK: B (fast)

try description.withUTF8 {
    try self.decode($0)
}

[oscbyspro]

The GCD stuff is a bit awkward to use in some generic contexts. I'll have a look a that, and perhaps hoist them like ilog2() and isqrt(). I also think it would be better if guarantee types mimicked their payload types w.r.t. instance vs static methods.

[oscbyspro]

Hm. Seems like I'll have to correct some change-of-sign stuff now that BinaryInteger/bezout(_:) permits signed values.

[oscbyspro]

I'll make TextInt's initializers generic over BinaryInteger but keep the UX default. I'll also change the radix output type to U8. The preferred concrete types minimize the need for size-related validation. The generics will remove the need for explicit type conversions.

[oscbyspro]

I'll add the following convenience conversions, which I performed manually in (#83).

extension BinaryInteger {
    @inlinable public static func exactly<Other>(
        _ source: consuming Fallible<Other>
    ) -> Fallible<Self> where Other: BinaryInteger { ... }

    @inlinable public static func exactly<Other>(
        sign: consuming Sign = .plus,
        magnitude: consuming Fallible<Other>
    ) -> Fallible<Self> where Other: UnsignedInteger { ... }
}

These should really be borrowing but that is not quite possible in ≤ Swift 5.10.