29 lines
635 B
TypeScript
29 lines
635 B
TypeScript
export function prop(object: Object, name: string, f: () => any): void {
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Object.defineProperty(object, name, {
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configurable: true,
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enumerable: true,
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get: function() {
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let value = f.call(this);
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this[name] = value;
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return value;
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},
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set: function(value) {
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Object.defineProperty(this, name, {
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configurable: true,
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enumerable: true,
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value: value,
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writable: true,
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});
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},
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});
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}
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export function value<T>(f: () => T): () => T {
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let value: T;
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return function(): T {
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if (value !== undefined) return value;
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value = f();
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return value;
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};
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}
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