20 lines
447 B
TypeScript
20 lines
447 B
TypeScript
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// https://www.codementor.io/@agustinchiappeberrini/lazy-evaluation-and-javascript-a5m7g8gs3
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export interface Lazy<T> {
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(): T
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isLazy: boolean
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}
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export const lazy = <T>(getter: () => T): Lazy<T> => {
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let evaluated: boolean = false
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let _res: T = null
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const res = <Lazy<T>>function (): T {
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if (evaluated) return _res
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_res = getter.apply(this, arguments)
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evaluated = true
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return _res
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}
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res.isLazy = true
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return res
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}
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