diff options
Diffstat (limited to 'lisp/subr.el')
| -rw-r--r-- | lisp/subr.el | 25 |
1 files changed, 20 insertions, 5 deletions
diff --git a/lisp/subr.el b/lisp/subr.el index 43a9fc015b1..b8b0d5af3b8 100644 --- a/lisp/subr.el +++ b/lisp/subr.el @@ -312,6 +312,26 @@ result of an actual problem." (while t (signal 'user-error (list (apply #'format format args))))) +(defun define-error (name message &optional parent) + "Define NAME as a new error signal. +MESSAGE is a string that will be output to the echo area if such an error +is signaled without being caught by a `condition-case'. +PARENT is either a signal or a list of signals from which it inherits. +Defaults to `error'." + (unless parent (setq parent 'error)) + (let ((conditions + (if (consp parent) + (apply #'nconc + (mapcar (lambda (parent) + (cons parent + (or (get parent 'error-conditions) + (error "Unknown signal `%s'" parent)))) + parent)) + (cons parent (get parent 'error-conditions))))) + (put name 'error-conditions + (delete-dups (copy-sequence (cons name conditions)))) + (when message (put name 'error-message message)))) + ;; We put this here instead of in frame.el so that it's defined even on ;; systems where frame.el isn't loaded. (defun frame-configuration-p (object) @@ -2526,11 +2546,6 @@ When the hook runs, the temporary buffer is current. This hook is normally set up with a function to put the buffer in Help mode.") -;; The `assert' macro from the cl package signals -;; `cl-assertion-failed' at runtime so always define it. -(put 'cl-assertion-failed 'error-conditions '(error)) -(put 'cl-assertion-failed 'error-message (purecopy "Assertion failed")) - (defconst user-emacs-directory (if (eq system-type 'ms-dos) ;; MS-DOS cannot have initial dot. |