Composable finalizer library.
trivial-garbage is a portable layer over a simple finalize concept. This builds upon that by creating a make-finalizers generic function which builds a list of finalizers to run for an object.
This allows building extensible finalization for objects.
Additionally, the define-finalizer macro helps in creating finalizers in the common pattern of closing-over slot values.
We can define a finalizer for a class with define-finalizer
;; Define a finalizer specialized on the class `net-logger',
;; which closes over the slots `sock' and `log-stream'
(define-finalizer net-logger (sock log-stream)
(usocket:socket-close sock)
(close log-stream))The library also defines a class finalizable, which automatically registers objects for finalization in its initialize-instance method:
(defclass my-file (finalizable)
(stream))
(define-finalizer my-file (stream)
(close stream))
;; The instance of `my-file' shall be registered for finalization
(make-instance 'my-file (open "foo.txt"))To register for finalization manually, there is the register-finalizer function:
(defclass my-file ()
(stream))
(define-finalizer my-file (stream)
(close stream))
(let ((my-file (make-instance 'my-file (open "foo.txt"))))
;; This will construct & register finalizer for `my-file`
(register-finalizer my-file))See LICENSE