Why would it print the colon?

Regex syntax and features vary between implementations. \d isn’t supported by BRE/ERE flavors.

GNU grep supports PCRE, so you can use grep -oP '/dev/loop\d' or grep -o '/dev/loop[0-9]' if you are matching only one digit character.

Thanks a lot for the feedback :)

Already done grep, sed, coreutils, cli basics and more. See https://learnbyexample.github.io/learn_gnuawk/buy.html#book-list for links.

Well, if you are comfortable with Python scripts, there’s not much reason to switch to awk. Unless perhaps you are equating awk to Python as scripting languages instead of CLI usage (like grep, sed, cut, etc) as my ebook focuses on. For example, if you have space separated columns of data, awk '{print $2}' will give you just the second column (no need to write a script when a simple one-liner will do). This of course also allows you to integrate with shell features (like globs).

As a practical example, I use awk to filter and process particular entries from financial data (which is in csv format). Just a case of easily arriving at a solution in a single line of code (which I then save it for future use).

Not my site, just sharing a link I saw on HN.

Well, I’m not going to even try understanding the various features used in that sed command. I do know how to use basic loops with labels, but I never bothered with all the buffer manipulation stuff. I’d rather use awk/perl/python for those cases.

This might work, but I think it is best to not tinker further if you already have a working script (especially one that you understand and can modify further if needed).

perl -pe 's/\[[^]]+\]\((?!https?)[^#]*#\K[^)]+(?=\))/lc $&=~s:%20|\d\K\.(?=\d):-:gr/ge'

Hmm, OP mentioned “Only edit what’s between parentheses” - don’t see anywhere that whole URL shouldn’t be changed…

Here’s a solution with perl (assuming you don’t want to change http/https after the start of ( instead of start of a line):

perl -pe 's/\[[^]]+\]\(\K(?!https?)[^)]+(?=\))/lc $&=~s|%20|-|gr/ge' ip.txt

• e flag allows you to use Perl code in the substitution portion.
• \[[^]]+\]\(\K match square brackets and use \K to mark the start of matching portion (text before that won’t be part of $&)
• (?!https?) don’t match if http or https is found
• [^)]+(?=\)) match non ) characters and assert that ) is present after those characters
• $&=~s|%20|-|gr change %20 to - for the matching portion found, the r flag is used to return the modified string instead of change $& itself
• lc is a function to change text to lowercase

GNU datamash (https://www.gnu.org/software/datamash/alternatives/) - handy tool for data munching. There’s also https://github.com/BurntSushi/xsv

Check out my chapter on GNU grep BRE/ERE for those wanting to learn this regex flavor: https://learnbyexample.github.io/learn_gnugrep_ripgrep/breere-regular-expressions.html (there’s also another chapter for PCRE)

See also https://github.com/TomWright/dasel

I use Vim ;)

Python itself provides IDLE, which is good enough for beginners. https://thonny.org/ is another good one for beginners.

As mentioned by others, Jetbrains is good for many languages. https://www.kdevelop.org/ is another option.

I wish you success. I’m happy to use SimpleScreenRecorder(https://github.com/MaartenBaert/ssr).

I have a list of learning resources for CLI tools and scripting here: https://learnbyexample.github.io/curated_resources/linux_cli_scripting.html

I’ve also written a few TUI interactive apps to practice text processing commands like grep, sed, awk, coreutils, etc: https://github.com/learnbyexample/TUI-apps

Why do you think it is a phishing link? Gumroad is a well known platform to sell digital goods.

I mention it is free up to some date because it will go back to being a paid product after that.

Is it regex or sed/awk syntax (or both) that gives you trouble?

I had similar reaction and didn’t even try to learn them for years - then I caught the stackoverflow craze of answering CLI questions (and learning from others).

oxipng, pngquant and svgcleaner for optimizing images

auto-editor for removing silent portions from video recordings

Not my blog, just sharing it here. Saw it on HN (https://news.ycombinator.com/item?id=40419325)