52 lines
2.1 KiB
Swift
52 lines
2.1 KiB
Swift
//
|
|
// Alphabet.swift
|
|
// Bases
|
|
//
|
|
// Copyright (c) 2016-2018 Matt Rubin and the Bases authors
|
|
//
|
|
// Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
// of this software and associated documentation files (the "Software"), to deal
|
|
// in the Software without restriction, including without limitation the rights
|
|
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
// copies of the Software, and to permit persons to whom the Software is
|
|
// furnished to do so, subject to the following conditions:
|
|
//
|
|
// The above copyright notice and this permission notice shall be included in all
|
|
// copies or substantial portions of the Software.
|
|
//
|
|
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
// SOFTWARE.
|
|
//
|
|
|
|
internal typealias Byte = UInt8
|
|
internal typealias EncodedChar = UInt8
|
|
|
|
internal let encodingTable: [EncodedChar] = [
|
|
48, 49, 50, 51, 52, 53, 54, 55,
|
|
56, 57, 65, 66, 67, 68, 69, 70,
|
|
]
|
|
|
|
private let __: Byte? = nil
|
|
private let decodingTable: [Byte?] = [
|
|
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
|
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
|
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
|
00, 01, 02, 03, 04, 05, 06, 07, 08, 09, __, __, __, __, __, __,
|
|
__, 10, 11, 12, 13, 14, 15, __, __, __, __, __, __, __, __, __,
|
|
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
|
__, 10, 11, 12, 13, 14, 15, __, __, __, __, __, __, __, __, __,
|
|
__, __, __, __, __, __, __, __, __, __, __, __, __, __, __, __,
|
|
]
|
|
|
|
internal func byte(decoding char: EncodedChar) throws -> Byte {
|
|
guard let byte = decodingTable[Int(char)] else {
|
|
throw Base16.Error.nonAlphabetCharacter
|
|
}
|
|
return byte
|
|
}
|