4 ms·

Ack - a faster, more featureful, grep

13 points by smanek 18y ago

neilc 18y ago
It seems like it is only faster because it applies a bunch of heuristics to avoid searching certain files and directories altogether. I use "ack" myself and it's quite nice, but the heuristics aren't perfect: ack won't search for strings inside yacc grammars (".y" files) by default, for example.
- smanek 18y ago
  True, part of the speed comes from it's (configurable) heuristics. But, it's faster even when doing the same thing. For example, see the benchmark at http://blog.i-no.de/archives/2008/05/06/index.html http://blog.i-no.de/archives/2008/05/06/index.html. Then end result is that, on the same search, ack is approximately 5 times faster than grep. I ran a few test cases myself and got similar results. But the real reason I like it is the perl compatible regexes. The differences between perl regexes and gnu regexes are just big enough to be an annoyance.
  - jrockway 18y ago
    It doesn't use "perl compatible regexes", it uses Perl.
    - smanek 18y ago
      I would argue that 'perl regexes' are a member of the set of 'perl compatible regexes' ;-)
      - donw 18y ago
        Proof? ;p
  - neilc 18y ago
    In that particular case, ack's performance advantage seems to arise mostly because of a bug that causes GNU grep to be terribly slow in multibyte locales: http://blog.i-no.de/archives/2008/05/07/index.html http://blog.i-no.de/archives/2008/05/07/index.html http://savannah.gnu.org/bugs/index.php?14472 http://savannah.gnu.org/bugs/index.php?14472
jobeirne 18y ago
Why do all these regex utilities sound like onomatopoeias for really obscene things?
bprater 18y ago
Wow, impressive homepage from a marketing angle. You hackerheads would do well to print out this website and hang it on your wall. Note the use of: quick, clear description; testimonials; subscribe box so you can keep in touch with the project; a top-ten list; and no-frills detailed information.
- chrisbroadfoot 18y ago
  I am a strong believer in having code examples on your front page. Ruby wins at this, as does Groovy.
uzi 18y ago
While we're on something that is essentially a more powerful "find and grep", I wrote this years ago: http://uzix.org/cgvg.html http://uzix.org/cgvg.html Like ack, it uses perl's regexes... just add more file extensions and you're golden. The nice thing is you do: cg pattern which gives you a list with what it found, which file, the line number and an index... then you vg index and it opens that file at that line.
swombat 18y ago
Is it possible to install it under Leopard without using Ports?
- smanek 18y ago
  yep, it's just straight perl, and Leopard comes with perl

13 points by smanek 18y ago

neilc 18y ago

It seems like it is only faster because it applies a bunch of heuristics to avoid searching certain files and directories altogether. I use "ack" myself and it's quite nice, but the heuristics aren't perfect: ack won't search for strings inside yacc grammars (".y" files) by default, for example.

smanek 18y ago
True, part of the speed comes from it's (configurable) heuristics. But, it's faster even when doing the same thing. For example, see the benchmark at http://blog.i-no.de/archives/2008/05/06/index.html http://blog.i-no.de/archives/2008/05/06/index.html. Then end result is that, on the same search, ack is approximately 5 times faster than grep. I ran a few test cases myself and got similar results. But the real reason I like it is the perl compatible regexes. The differences between perl regexes and gnu regexes are just big enough to be an annoyance.
- jrockway 18y ago
  It doesn't use "perl compatible regexes", it uses Perl.
  - smanek 18y ago
    I would argue that 'perl regexes' are a member of the set of 'perl compatible regexes' ;-)
    - donw 18y ago
      Proof? ;p
- neilc 18y ago
  In that particular case, ack's performance advantage seems to arise mostly because of a bug that causes GNU grep to be terribly slow in multibyte locales: http://blog.i-no.de/archives/2008/05/07/index.html http://blog.i-no.de/archives/2008/05/07/index.html http://savannah.gnu.org/bugs/index.php?14472 http://savannah.gnu.org/bugs/index.php?14472

jobeirne 18y ago

Why do all these regex utilities sound like onomatopoeias for really obscene things?

bprater 18y ago

Wow, impressive homepage from a marketing angle. You hackerheads would do well to print out this website and hang it on your wall. Note the use of: quick, clear description; testimonials; subscribe box so you can keep in touch with the project; a top-ten list; and no-frills detailed information.

chrisbroadfoot 18y ago
I am a strong believer in having code examples on your front page. Ruby wins at this, as does Groovy.

uzi 18y ago

While we're on something that is essentially a more powerful "find and grep", I wrote this years ago: http://uzix.org/cgvg.html http://uzix.org/cgvg.html Like ack, it uses perl's regexes... just add more file extensions and you're golden. The nice thing is you do: cg pattern which gives you a list with what it found, which file, the line number and an index... then you vg index and it opens that file at that line.

swombat 18y ago

Is it possible to install it under Leopard without using Ports?

smanek 18y ago
yep, it's just straight perl, and Leopard comes with perl