KeyExistsQ¶

Status: Stable

documented, exercised by the test suite and/or worked examples, with no known limitations recorded.

Description¶

KeyExistsQ[assoc, key]

Gives True if key is present in assoc, else False.

Every input below was run against the current Mathilda build and its output recorded.

In[1]:= KeyExistsQ[<|"a" -> 1|>, "a"]
Out[1]= True

In[2]:= KeyFreeQ[<|"a" -> 1|>, "b"]
Out[2]= True

Attributes: Protected.

See also: KeyMemberQ, KeyFreeQ