simple-vector-p

(simple-vector-p object)

Returns true when object is a SIMPLE vector: a rank-1 array with element type t, no fill pointer, not :adjustable, and not displaced. A vector literal and a plain make-array result are simple; a string (element type character), a packed vector, a fill-pointered or adjustable array, and a displaced view are not. It answers exactly what (typep object 'simple-vector) does.