counting.swift

import Cocoa

func enumCount<EnumType:Hashable>(eType : EnumType.Type) -> Int {
    if sizeof(eType) == 0 {return 1}
    if sizeof(eType) == 1 {
        for hashIndex in 2..<(2 << 8) {
            if unsafeBitCast(UInt8(hashIndex), eType).hashValue == 0 {
                return hashIndex}
        }
        return 2 << 8
    }
    if sizeof(eType) > 2 {return -1}
    for hashIndex in ((2 << 8) + 1)..<(2 << 16) {
        if unsafeBitCast(UInt8(hashIndex), eType).hashValue == 0 {
            return hashIndex}
    }
    return 2 << 16
}

func members<EnumType:Hashable>(eType:EnumType.Type) -> [EnumType] {
    var m = [EnumType]()
    for i in 0..<enumCount(EnumType) {
        let j = unsafeBitCast(UInt8(i), EnumType.self)
        m.append(j)
    }
    return m
}

enum Planets : Int {case Mercury, Venus, Earth, Mars, Jupiter, Saturn, Neptune, Uranus, Pluto}
enum Foo : Int {case i = 1, j = 5, k = 9}
enum Coin {case Heads, Tails}
enum Quark: String {case Up, Down, Top, Bottom, Strange, Charmed}

print(members(Planets))
print(members(Foo))
print(members(Coin))
print(members(Quark))