Decomposing compound questions
The basis of the Unix philosophy is to decompose complex tasks into simple sub-tasks, so that one can easily choose a combination of simple Unix tools to solve the problem in an intuitive way.
Often I see newbies ask questions along the lines of "how do I X complicated and specific thing". The greybeards then oblige with an even more complicated and impenetrable one liner. The newbie is left with a renewed conviction that the Unix command line is magic, and only a wizened old shell-master, who has spent his life memorizing every man page, can hope to use its powers.
The Unix command line is not a magician's riddle. You're not supposed to "just know" exactly the right obscure incantation for every situation, and if you don't then it's your punishment to do things by hand. It's supposed to be a powerful, intuitive toolkit that works together with the natural problem solving and analysis abilities of your brain.
Whenever someone asks how to do X in the shell, it should be a valid and preferred answer to explain that:
- X is actually a combination of tasks Y and Z
- Link to questions about doing Y, and questions about doing Z
- Explain how to combine them together (eg. with pipes)
The alternative is that for N types of problems, we will end up answering N + N*N + N*N*N + ... questions for every combination of them. That is silly, clogs up the site with tedious junk, and does a great pedagogical disservice to new Unix users. Instead we should simply have N questions explaining each simple task, and a handful more to explain how to compose them together.
As an example, imagine questions like:
- How do I delete every file that meets X condition
- How do run a conversion program on every file of type Y
- How do I get the file counts of every file in these directories
- Infinitely many variations
These all come down to the same thing:
- How can I obtain a list of paths? (refer to
find,fd,ls...) - How do I filter a list of paths based on criteria? (
findarguments, shellif, many others) - How can I run a program on every file? (refer to pipes,
xargs, Shell expansion, GNUparallel, Shellfor...) - How can I do X task on Y file? (obvious, but refer to
rm, etc)
The only real answer that needs to be given to such questions is to explain how to decompose the task into more obvious sub-tasks, how to pick appropriate Unix tools for those sub-tasks and how to combine them.
As a FOSS advocate, I find it frankly shameful and reprehensible that a community for helping Unix users would keep the wonderful concept of the Unix philosophy a secret from newbies, for the sole reason that the newbies did not think to explicitly ask about it without knowing its existence. Maybe on codidact we can do better?
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