ag

The Silver Searcher. Like ack, but aims to be faster. More information: https://github.com/ggreer/the_silver_searcher.

• Find files containing "foo", and print the line matches in context:
  ag {{foo}}
• Find files containing "foo" in a specific directory:
  ag {{foo}} {{path/to/directory}}
• Find files containing "foo", but only list the filenames:
  ag -l {{foo}}
• Find files containing "FOO" case-insensitively, and print only the match, rather than the whole line:
  ag -i -o {{FOO}}
• Find "foo" in files with a name matching "bar":
  ag {{foo}} -G {{bar}}
• Find files whose contents match a regular expression:
  ag '{{^ba(r|z)$}}'
• Find files with a name matching "foo":
  ag -g {{foo}}