23 lines
327 B
TypeScript
23 lines
327 B
TypeScript
class Narrow {
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narrowed: boolean
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}
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var a: object
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if (a instanceof Narrow) {
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a.narrowed; // ok
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a = 123; // error
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}
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if (typeof a === 'number') {
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a.toFixed(); // error, never
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}
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var b: object | null
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if (typeof b === 'object') {
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b.toString(); // ok, object | null
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} else {
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b.toString(); // error, never
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}
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