Refactoring

This commit is contained in:
Justin Mazzocchi 2020-09-26 15:56:24 -07:00
parent 3f0f19a75b
commit 718dfccf7d
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GPG key ID: E223E6937AAFB01C

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@ -17,18 +17,18 @@ extension BitArray {
subscript(index: Int) -> Bool {
get {
let (byteIndex, bitIndex) = index.quotientAndRemainder(dividingBy: UInt8.bitWidth)
let (byteIndex, mask) = Self.byteIndexAndMask(index: index)
return bytes[byteIndex] & Self.mask(bitIndex: bitIndex) > 0
return bytes[byteIndex] & mask > 0
}
set {
let (byteIndex, bitIndex) = index.quotientAndRemainder(dividingBy: UInt8.bitWidth)
let (byteIndex, mask) = Self.byteIndexAndMask(index: index)
if newValue {
bytes[byteIndex] |= Self.mask(bitIndex: bitIndex)
bytes[byteIndex] |= mask
} else {
bytes[byteIndex] &= ~Self.mask(bitIndex: bitIndex)
bytes[byteIndex] &= ~mask
}
}
}
@ -47,7 +47,10 @@ extension BitArray: Codable {
}
private extension BitArray {
static func mask(bitIndex: Int) -> UInt8 {
UInt8(2 << (bitIndex - 1))
static func byteIndexAndMask(index: Int) -> (Int, UInt8) {
let (byteIndex, bitIndex) = index.quotientAndRemainder(dividingBy: UInt8.bitWidth)
let mask = UInt8(2 << (bitIndex - 1))
return (byteIndex, mask)
}
}