23 lines
410 B
TypeScript
23 lines
410 B
TypeScript
export function lazy<T>(fn: () => T) {
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let value: T | undefined
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let loaded = false
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const result = (): T => {
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if (loaded) return value as T
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try {
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value = fn()
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loaded = true
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return value as T
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} catch (e) {
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// Don't mark as loaded if initialization failed
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throw e
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}
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}
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result.reset = () => {
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loaded = false
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value = undefined
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}
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return result
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}
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