Configuration

Highlighting results

ag.el supports highlighting results for ag 0.14 or later. Previous versions of ag don’t support the --color-match argument.

If your version of ag is recent enough, you can add highlighting by adding the following to your Emacs configuration:

(setq ag-highlight-search t)

Path to the ag executable

ag.el assumes that the ag executable is in one of the directories on exec-path. Generally, this is sufficient.

However, you may find that you can run ag in a terminal but ag.el isn’t finding the ag executable. This is common on Mac OS X. You’ll need to update exec-path to match your terminal. The best way to do this is to install exec-path-from-shell (available on MELPA).

Alternatively, you can do this yourself by putting the following code in your Emacs configuration:

(defun set-exec-path-from-shell-PATH ()
  "Set up Emacs' `exec-path' and PATH environment variable to match that used by the user's shell.

This is particularly useful under Mac OSX, where GUI apps are not started from a shell."
  (interactive)
  (let ((path-from-shell (replace-regexp-in-string "[ \t\n]*$" "" (shell-command-to-string "$SHELL --login -i -c 'echo $PATH'"))))
    (setenv "PATH" path-from-shell)
    (setq exec-path (split-string path-from-shell path-separator))))

(set-exec-path-from-shell-PATH)

Finally, as a last resort, you can specify the path to ag explicitly. This might be the case if:

  • you are are in an environment where, for whatever reason, you can’t easily change the path to include ag
  • you are on windows, where the executable name ends in .exe.
  • you have multiple versions of ag or want to use some other executable that works the same as ag.

To change the ag executable used:

(setq ag-executable "C:/Wherever/I/Installed/Ag/ag.exe")

Visiting the results

By default, ag.el will open results in a different window in the frame, so the results buffer is still visible. You can override this so the results buffer is hidden and the selected result is shown in its place:

(setq ag-reuse-window 't)

Overriding the arguments passed to ag

ag.el provides a customisable variable ag-arguments.

For temporary changes to arguments, the search commands will prompt you for arguments if you call them with a prefix argument. For example, C-u M-x ag.

Hooks

ag.el provides ag-mode-hook which is run when you start a search, and ag-search-finished-hook which is run when the search completes.

Multiple search buffers

Ag.el provides the interactive commands for closing old search buffers:

  • ag-kill-buffers
  • ag-kill-other-buffers

Alternatively, you can make ag.el reuse the same *ag* buffer for all your searches:

(setq ag-reuse-buffers 't)