Table of Contents generated with autotoc

ag.el

ag.el

A simple ag frontend, loosely based on ack-and-half.el.

Screenshot

Usage

Installation

You can install ag.el from MELPA or Marmalade. Just run M-x package-install RET ag RET. Functions are autoloaded, so (require 'ag) is unnecessary.

If you want to install it manually, add the following to your .emacs.d:

(add-to-list 'load-path "/path/to/ag.el")
(require 'ag)

Running a search

You will now have the following interactive commands available for performing searches:

ag
ag-files
ag-regexp
ag-project
ag-project-files
ag-project-regexp

*-project commands automatically choose the directory to search, automatically detecting git, Subversion and Mercurial project roots.

*-files commands allow you to specify a PCRE pattern for files to search in. By default, ag searches in all files. Note that in both cases, ag ignores files that are ignored by your VCS (e.g. things mentioned in .gitignore).

The results buffer

In the search results buffer, you can move between results by pressing n and p, and you can visit the file by pressing <return> or clicking.

You can run the search again by pressing g, or close the buffer with q.

You can activate next-error-follow-minor-mode with C-c C-f. With this minor mode enabled, moving in the results buffer will make Emacs automatically display the search result at point.

If you've configured wgrep you can use C-c C-p to make the buffer writable and edit the results inline.

Of course, C-h m inside a results buffer witll show all the keybindings available to you.

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 both Marmalade and 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)

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)

Hooks

ag.el provides ag-mode-hook which is run when you start a search.

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)

Using with Projectile

Projectile supports ag.el. If you have Projectile installed, C-c p A runs ag on your project.

Customising the project root

By default, ag-project and ag-project-regexp use the root of the VCS repo as the directory to search in. You can override this by setting or customising ag-project-root-function.

Using ag in elisp functions

You can use ag, ag-project and so on from an elisp function. ag/FOO functions are private and are more likely to change. Please file a bug if you find a use for internal functions that you can't do otherwise.

Editing the results inline

wgrep has support for ag.el. If you install wgrep-ag (available on MELPA), you can simply run wgrep-change-to-wgrep-mode and edit the *ag* buffer. Press C-x C-s when you're done to make the changes to buffers.

Changelog

0.35

Added the ag-files and ag-project-files commands.

Note that the internal API changed in this release: ag/search now takes regexp as a keyword argument instead of a positional argument. I'm not aware of any external packages depending on this, so I'm not incrementing the major version.

0.34

Specifying the path as an argument to ag, allowing ag.el to do searches on Windows.

0.33

Fixed a bug with ag.el not searching if shell-command-switch had been modified by the user.

0.32

Adding ag-project-root-function which allows users to override how ag.el finds the root of a project.

0.31

Ag.el faces (which are ag-match-face and ag-hit-facex) are defined with defface, so you can use customize-face on them.

0.30

Improved quoting of arguments passed to ag.

0.29

Added customisable variable ag-reuse-window. If set to t (defaults to nil) then selecting a search result hides the results buffer and shows the match, rather than using a different window in the frame.

0.28

-project functions now handle the case of multiple nested VCS repositories. Ag.el now takes the most deepest subdirectory, so if /foo/bar is a subversion repo that contains a git repo /foo/bar/baz, ag.el will search /foo/bar/baz.

0.27

Ag.el autopopulates the minibuffer with the text at point, or the active selection. If this text was read-only, the minibuffer text would also be read-only. It's now always possible to edit the text in the minibuffer.

0.26

Fixed a crash when refreshing a search buffer by pressing g.

0.25

Added commands ag-kill-buffers and ag-kill-other-buffers to close old search result buffers. Also added a customisable variable ag-reuse-buffers so users can optionally stop ag.el creating multiple buffers.

0.24

Search results buffers now take the form *ag text:something dir:~/some/path*, so new searches will create new buffers.

0.23

ag.el now detects the project root for Mercurial repositories in the ag-project* commands.

0.22

The keys n and p now move between matches, similar to the behaviour of dired.

0.21

Added a new face ag-hit-face to distinguish from ag-match-face.

0.20

Fixed next-error and previous-error not working with ag.el (broken in v0.18).

0.19

ag now has a default search term of the symbol at point.

0.18

Search results are now highlighted as information, rather than errors. The ag output is now more consistent with grep.el.

0.17

The interactive functions provided by ag.el are now autoloaded.

0.16

Removed the unused variable ag-last-buffer

0.15

Fixed ag-project and ag-project-regexp not working in buffers that aren't associated with a specific file, such as dired and magit buffers.

0.14

The compilation mode regexp is now more accurate, so you should no longer get 'compilation-next-error: No error here' when trying to open a file in the results list.

0.13

Current stable ag (0.13.1) doesn't support --color-match, ag.el now only highlights when ag-highlight-search is non-nil (the default is nil).

If you're upgrading ag.el and your ag version is 0.14 or higher, you need to explicitly enable highlighting:

(setq ag-highlight-search t)

Alternatives

There's an ag plugin for helm: https://github.com/syohex/emacs-helm-ag

Todo

Remove *-at-point commands in favour of always defaulting to the symbol at point.
Add aliases for the old command names to ensure backward compatibility.
Modify ag-regexp-project-at-point to quote the default search string, otherwise "foo.bar" will match other things.