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What does the delete operator do?

Q: What does the delete operator do?

**Core concept (TL;DR).** delete removes a **property** from an object and returns true on success. That's its whole job — it does **not** delete variables, functions, or free memory, and on an array it removes the element but leaves a *hole* (the length doesn't change). delete removes a property — and leaves array holes delete obj.b <text x="135" y="84" fill

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