KeyFreeQ

KeyFreeQ[assoc, form] yields True if no key in the association assoc matches form, and yields False otherwise.

• KeyFreeQ[form] represents an operator form of KeyFreeQ that can be applied to an expression.

Examples

KeyFreeQ[<|"a" -> 1, "b" -> 2|>, "c"]

KeyFreeQ[<|1 -> "x", 2 -> "y"|>, _String]

Please visit the official Wolfram Language Reference for more details.