objc:objectp

(objc:objectp value)

Whether the value is an objc:objc-object-pointer -- an object or a class (objc:objc-class is a subtype). A selector, a string, and an objc:standard-objc-object (whose pointer objc:objc-object-pointer answers) are not. It touches no runtime, so it works on every machine. Not in LispWorks' interface. Part of the macOS-only objc package -- the interpreter (java -jar, or the rontolisp native binary), a compiled .class / .jar and a --native executable for macOS on Apple silicon, never a .wasm. See the macOS GUI guide.

CL-USER> (objc:objectp (objc:string-to-ns-string "x"))
T
CL-USER> (objc:objectp (objc:coerce-to-objc-class "NSString"))
T
CL-USER> (objc:objectp (objc:coerce-to-selector "length"))
NIL
CL-USER> (objc:objectp "x")
NIL