Some useful extensions to Dictionary

dictext.swift

extension Dictionary {
	init (_ array: Array<Element>) {
		self = [ : ]
		self.merge(array)
	}
	
	mutating func merge (array: Array<Element>) {
		for (key: KeyType, value: ValueType) in array {
			self[key] = value
		}
	}
	
	init <S: Sequence where S.GeneratorType.Element == Element> (_ seq: S) {
		self = [ : ]
		self.merge(seq)
	}
	
	mutating func merge <S: Sequence where S.GeneratorType.Element == Element> (seq: S) {
		var gen = seq.generate()
		while let (key: KeyType, value: ValueType) = gen.next() {
			self[key] = value
		}
	}
}

// Example:

let nums = [0, 1, 2, 3]
let mp = map(nums, {($0 * 2, "“\($0)”")})
let dm = Dictionary(mp)
println(dm)	// will print [0: “0”, 2: “1”, 4: “2”, 6: “3”]

// The merge functions act on an existing (mutable) Dictionary instead of
// returning a new one.