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27 lines
526 B
Markdown
27 lines
526 B
Markdown
---
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date: 20201116
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id: 653df156-531e-48c9-a637-a1609069ff8e
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title: Optional Chaining Operator (?.)
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---
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# Description
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Permits reading the value of a property located within a chain of
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connected objects without having to expressly validate that each
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reference in the chain is valid.
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# Syntax
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``` javascript
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const adventurer = {
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name: "Alice",
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cat: {
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name: "Dinah",
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},
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};
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const dogName = adventurer.dog?.name;
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console.log(dogName); // undefined
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console.log(adventurer.someNonExistentMethod?.()); // undefined
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```
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