This package provides an Emacs interface to the command-line tool ack.

From <http://betterthangrep.com/>: ack is a tool like grep, designed
for programmers with large trees of heterogeneous source code.  ack is
written purely in Perl, and takes advantage of the power of Perl's
regular expressions.

Usage:
Type `M-x ack' and provide a pattern to search.
Type `C-u M-x ack' to search from current project root.
Type `C-u C-u M-x ack' to interactively choose a directory to search.

While reading ack command and args from the minibuffer, the following
key bindings may be useful:

- `M-I' inserts a template for case-insensitive file name search
- `M-G' inserts a template for `git grep', `hg grep' or `bzr grep'
- `TAB' completes ack options

This package does not require `--nogroup' nor `--noheading'.
Coloring is performed using the standard library ansi-color.el.

Screenshots:
http://i.imgur.com/mrk8k.png
http://i.imgur.com/a72Ap.png
http://i.imgur.com/U2vFz.png

Bugs:
https://github.com/leoliu/ack-el/issues

ack.el was written by Leo Liu, with contributions from Phillip Lord.