expected-type.lisp

(in-package :cl-user)

(defstruct foo a)

(defun expected-type (fun)
  (handler-case (funcall (typecase fun
                           (function fun)
                           (symbol (symbol-function fun))
                           (t nil))
                         nil)
    (type-error (c) (type-error-expected-type c))))

(format t "~&;; ~A ~A => Type: ~A~%"
        (lisp-implementation-type)
        (lisp-implementation-version)
        (expected-type 'foo-a))

;; Results came from C-u C-x C-e
;; (slime-eval-last-expression)

;; SBCL 2.0.7 => Type: FOO
;; ECL 20.4.24 => Type: FOO
;; Armed Bear Common Lisp 1.7.1 => Type: STRUCTURE-OBJECT

;; Question:
;; Is it a bug for ABCL or implementation-dependent for TYPE-ERROR-EXPECTED-TYPE?