gives True if the head of expr is List, and False otherwise.


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Basic Examples  (2)

ListQ gives True when the head of an expression is List:

ListQ gives False when the head of an expression is not List:

ListQ gives False on other array representations:

Properties & Relations  (3)

ListQ is equivalent to MatchQ[#,_List]&:

VectorQ returns True for other 1D array representations:

ListQ[list] is not affected by deeper levels of List:

VectorQ[list] does not accept deeper levels of List:

Introduced in 1991