Created
April 14, 2016 18:59
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Lightweight generic cache
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// | |
// ThinCache.swift | |
// Planned | |
// | |
// Created by Quinn McHenry on 4/10/16. | |
// Copyright © 2016 Quinn McHenry. All rights reserved. | |
// | |
final class ThinCache<T> { | |
private var cached: Optional<T> | |
let generator: Void -> T | |
init(generator: Void -> T) { | |
self.generator = generator | |
} | |
func generate() -> T { | |
let t = generator() | |
cached = t | |
return t | |
} | |
func invalidate() { | |
cached = nil | |
} | |
var value: T { | |
get { | |
guard let cached = cached else { return generate() } | |
return cached | |
} | |
} | |
} |
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