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I understand the usefulness of this kind of command listing for people who just use sed occasionnaly and want to quickly copy/paste something still I think just

I understand the usefulness of this kind of command listing for people who just use sed occasionnaly and want to quickly copy/paste something still I think just learning how sed works is actually easier than treating it like magic. It's not awk. Sed is both logical and simple. Sed is the silent version of ed. It's a full line-oriented editor. You give it commands and it executes them on lines, one line at a time. Commands always have the same form: [lines range] [action][parameters] You just have to learn how ranges are defined and what the actions are then you can check the documentation for what the parameters are when you need to and you will be good to go forever. As a bonus, once you realize there is more actions than just s for substitute, you start realizing that people sometimes do very convoluted things with sed because they don't know how to use the other actions. For example, there are actions to join lines (j), to delete lines (d), to prefilter lines based on a regex (g and G).

twic 5y ago
> I think just learning how sed works is actually easier than treating it like magic. It's not awk. As someone with over a decade of heavy sed use, who only got into awk recently, i'd say awk is far easier and less magical. Awk is just another programming language, for the most part. Using sed for anything substantial requires you to think in strange directions, to find ways to thread state and control flow through the tiny holes the language gives you.
- WastingMyTime89 5y ago
  I think I both agree and disagree. As you rightfully pointed, I wouldn’t do anything overly complicated with sed because it really is a line editor and anything which is not line based and can’t be explained simply in the context of using an editor will quickly seem clunky and overly complicated. I wouldn’t do anything period with awk. I agree with you that it’s just another programming language but one which feels extremely dated with both a terrible syntax and awkward semantics. The rare times I have encountered something done with awk it was either so simple it should have been done with sed or so complicated I wish a proper scripting language like python or perl would have been used instead. As far as I’m concerned, awk is a tool without a proper use-case. It’s always better to use something else.
  - twic 5y ago
    Interesting! I don't find awk too strange; indeed i strongly prefer it to Perl, which i wrote a lot of around the turn of the century. These days i reach for awk for a lot of log processing, particularly when it needs to be stateful. For example, i have a log file with entries for remote clients connecting and disconnecting. An awk script can loop over that and keep an array of clients, adding and removing them as appropriate, and be easily tweaked to report different things - emit an event for each connection-disconnection pair, or track the number of clients connected over time, etc. I couldn't do that at all with sed. It would be more awkward with bash. It would be easy enough, if a little bit more verbose, in Python.

twic 5y ago

> I think just learning how sed works is actually easier than treating it like magic. It's not awk. As someone with over a decade of heavy sed use, who only got into awk recently, i'd say awk is far easier and less magical. Awk is just another programming language, for the most part. Using sed for anything substantial requires you to think in strange directions, to find ways to thread state and control flow through the tiny holes the language gives you.

WastingMyTime89 5y ago
I think I both agree and disagree. As you rightfully pointed, I wouldn’t do anything overly complicated with sed because it really is a line editor and anything which is not line based and can’t be explained simply in the context of using an editor will quickly seem clunky and overly complicated. I wouldn’t do anything period with awk. I agree with you that it’s just another programming language but one which feels extremely dated with both a terrible syntax and awkward semantics. The rare times I have encountered something done with awk it was either so simple it should have been done with sed or so complicated I wish a proper scripting language like python or perl would have been used instead. As far as I’m concerned, awk is a tool without a proper use-case. It’s always better to use something else.
- twic 5y ago
  Interesting! I don't find awk too strange; indeed i strongly prefer it to Perl, which i wrote a lot of around the turn of the century. These days i reach for awk for a lot of log processing, particularly when it needs to be stateful. For example, i have a log file with entries for remote clients connecting and disconnecting. An awk script can loop over that and keep an array of clients, adding and removing them as appropriate, and be easily tweaked to report different things - emit an event for each connection-disconnection pair, or track the number of clients connected over time, etc. I couldn't do that at all with sed. It would be more awkward with bash. It would be easy enough, if a little bit more verbose, in Python.