JS Built-ins
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Mapdeletebeginner

Map delete() β€” returns false for missing

πŸ“– Usage Example
const m = new Map([['a', 1], ['b', 2]])
m.delete('a')   // β†’ true
m.delete('z')   // β†’ false
console.log(m.size) // β†’ 1

Use Map.delete() to remove a key; it returns true if the key existed.

Map.prototype.delete()

delete() returns false when the key does not exist.

Challenge: Verify that delete() returns false for a missing key.

πŸ’‘ Hints (1)
  • β€’ delete() returns false (not undefined) when the key did not exist