objc:release

(objc:release pointer)

Gives up one reference the pointer holds -- an explicit retain first, else the one the object arrived with -- and sends release. A pointer holding none signals instead of over-releasing, so manual-style code cannot release twice what the collector would release once. An autorelease pool from objc:make-autorelease-pool is drained instead. 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; on a machine without the runtime it signals an error. See the macOS GUI guide.

CL-USER> (objc:release *o*)
NIL
CL-USER> (objc:release *o*)
NIL
CL-USER> (objc:release *o*)
error: objc:release: #<Pointer: OBJC:OBJC-OBJECT-POINTER = #x0000600000C04010> holds no reference this program can give up