Variable: backtrace-mode-hook

backtrace-mode-hook is a variable defined in backtrace.el.gz.

Value

nil

Documentation

Hook run after entering backtrace-mode.

No problems result if this variable is not bound. add-hook automatically binds it. (This is true for all hook variables.)

Source Code

;; Defined in /usr/src/emacs/lisp/emacs-lisp/backtrace.el.gz
;;; The mode definition

(define-derived-mode backtrace-mode special-mode "Backtrace"
  "Generic major mode for examining an Elisp stack backtrace.
This mode can be used directly, or other major modes can be
derived from it, using `define-derived-mode'.

In this major mode, the buffer contains some optional lines of
header text followed by backtrace frames, each consisting of one
or more whole lines.

Letters in this mode do not insert themselves; instead they are
commands.
\\<backtrace-mode-map>
\\{backtrace-mode-map}

A mode which inherits from Backtrace mode, or a command which
creates a `backtrace-mode' buffer, should usually do the following:

 - Set `backtrace-revert-hook', if the buffer contents need
   to be specially recomputed prior to `revert-buffer'.
 - Maybe set `backtrace-insert-header-function' to a function to create
   header text for the buffer.
 - Set `backtrace-frames' (see below).
 - Maybe modify `backtrace-view' (see below).
 - Maybe set `backtrace-print-function'.

A command which creates or switches to a Backtrace mode buffer,
such as `ert-results-pop-to-backtrace-for-test-at-point', should
initialize `backtrace-frames' to a list of `backtrace-frame'
objects (`backtrace-get-frames' is provided for that purpose, if
desired), and may optionally modify `backtrace-view', which is a
plist describing the appearance of the backtrace.  Finally, it
should call `backtrace-print'.

`backtrace-print' calls `backtrace-insert-header-function'
followed by `backtrace-print-frame', once for each stack frame."
  :syntax-table emacs-lisp-mode-syntax-table
  (when backtrace-fontify
    (setq font-lock-defaults
          '((backtrace-font-lock-keywords
             backtrace-font-lock-keywords-1
             backtrace-font-lock-keywords-2)
            nil nil nil nil
	    (font-lock-syntactic-face-function
	     . lisp-font-lock-syntactic-face-function))))
  (setq truncate-lines t)
  (buffer-disable-undo)
  ;; In debug.el, from 1998 to 2009 this was set to nil, reason stated
  ;; was because of bytecode. Since 2009 it's been set to t, but the
  ;; default is t so I think this isn't necessary.
  ;; (set-buffer-multibyte t)
  (setq-local revert-buffer-function #'backtrace-revert)
  (setq-local filter-buffer-substring-function #'backtrace--filter-visible)
  (setq-local indent-line-function 'lisp-indent-line)
  (setq-local indent-region-function 'lisp-indent-region)
  (add-function :around (local 'cl-print-expand-ellipsis-function)
                #'backtrace--expand-ellipsis)
  (add-hook 'xref-backend-functions #'backtrace--xref-backend nil t))