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32 lines
622 B
Markdown
32 lines
622 B
Markdown
---
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date: 2020-08-26
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id: 7b46ba87-7328-479c-8d79-badb24ed7b19
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title: JavaScript object operators
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---
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# Delete operator
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The `delete` operator deletes a binding (duh)
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``` javascript
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let anObject = {left: 1, right: 2};
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console.log(anObject.left);
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delete anObject.left;
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console.log(anObject.left);
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console.log("left" in anObject);
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console.log("right" in anObject);
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```
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# In operator
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The `in` operator tells you whether and object has a property with that
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name
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``` javascript
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let Object = {
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thisPropertyExists: true
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}
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console.log("thisPropertyExists" in Object)
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console.log("thisPropertyDoesNotExist" in Object)
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```
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