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Sed - An Introduction and Tutorial

• martythemaniak 18y ago
  Here is a command that really opened my eyes to how cool sed, grep and piping are: ls -R | grep ":$" | sed -e 's/:$//' -e 's/[^-][^\/]*\//--/g' -e 's/^/ /' -e 's/-/|/' courtesy of this site: http://www.centerkey.com/tree/ http://www.centerkey.com/tree/
  • silentbicycle 18y ago
    This ties in nicely to the threads about the necessity of comments. :) As a bonus, most (all?) of the sed commands are also usable in vi's ex mode (the : prompt).
• scott_s 18y ago
  How much value is there in learning sed when you go to languages like Perl or Python for such tasks?
  • silentbicycle 18y ago
    Perl works as a hyper-sed, but I think sed and Python are apples and oranges.
    • scott_s 18y ago
      Python gives me access to a complete regular expressions engine just as Perl does.
      • silentbicycle 18y ago
        I know. So does OCaml. Perl is a lot closer in character to sed and awk than Python is, though. That's all. I really dislike Perl, but I'm quite happy with using Python for general scripting and using sed for quick regex piping tasks. If I used Perl instead of Python, I probably wouldn't bother using sed. Perl has a lot of syntactic sugar for quick-and-dirty regex stuff, derived directly from sed and awk, while Python instead has sugar for list slicing, dictionaries, etc., but uses function syntax (e.g., re.search(pattern, string)) for regexes. I would rather have great syntax for lists and dicts, personally.