27 lines
330 B
JavaScript
27 lines
330 B
JavaScript
const obj = {
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a: {
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b: {
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c: {
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d: 2,
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},
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},
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},
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};
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const a = obj?.a;
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assert.equal(a, obj.a);
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const b = obj?.a?.b;
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assert.equal(b, obj.a.b);
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const bad = obj?.b?.b;
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assert.equal(bad, undefined);
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let val;
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val = obj?.a?.b;
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assert.equal(val, obj.a.b);
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assert.throws(() => {
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const bad = obj?.b.b;
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});
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