castanyes blaves

Top 10 reasons to use ack instead of grep.

1. It's blazingly fast because it only searches the stuff you want searched.
2. ack is pure Perl, so it runs on Windows just fine.
3. The standalone version uses no non-standard modules, so you can put it in your ~/bin without fear.
4. Searches recursively through directories by default, while ignoring .svn, CVS and other VCS directories.
* Which would you rather type?
$ grep pattern $(find . -type f | grep -v '\.svn')
$ ack pattern
5. ack ignores most of the crap you don't want to search
* VCS directories
* blib, the Perl build directory
* backup files like foo~ and #foo#
* binary files, core dumps, etc
6. Ignoring .svn directories means that ack is faster than grep for searching through trees.
7. Lets you specify file types to search, as in --perl or --nohtml.
* Which would you rather type?
$ grep pattern $(find . -name '*.pl' -or -name '*.pm' -or -name '*.pod' | grep -v .svn)
$ ack --perl pattern
Note that ack's --perl also checks the shebang lines of files without suffixes, which the find command will not.
8. File-filtering capabilities usable without searching with ack -f. This lets you create lists of files of a given type.
$ ack -f --perl > all-perl-files
9. Color highlighting of search results.
10. Uses real Perl regular expressions, not a GNU subset.
11. Allows you to specify output using Perl's special variables
* Example: ack '(Mr|Mr?s)\. (Smith|Jones)' --output='$S'
12. Many command-line switches are the same as in GNU grep:
-w does word-only searching
-c shows counts per file of matches
-l gives the filename instead of matching lines
etc.
13. Command name is 25% fewer characters to type! Save days of free-time! Heck, it's 50% shorter compared to grep -r.