[Amendment] SE-0368: StaticBigInt

[tera]

Very interesting, and somewhat unexpected. Example:

struct OnesComplement: ExpressibleByIntegerLiteral {
    init(integerLiteral value: Int) {
        self.value = value
    }
    init(value: Int) {
        self.value = value
    }
    var value: Int
    
    static prefix func - (a: Self) -> Self {
        return Self(value: ~a.value)
    }
}

let one: OnesComplement = 1
print("1 ==", one.value)        // 1 ==  1
let a: OnesComplement = -one
print("-2 ==", a.value)         // -2 == -2
let b: OnesComplement = -(1 as OnesComplement)
print("-2 ==", b.value)         // -2 == -2
let c: OnesComplement = -1
print("-2 ==", c.value)         // -2 == -1  🤔?!
print()

Edit: the workaround is simple of course.

    init(integerLiteral value: Int) {
        self.value = value < 0 ? ~(-value) : value
    }