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Comment by vultour | Hacker News Reader

Honestly, I don't think I found a single case where this was true. Every time I try to rewrite a moderately complex bash script in Python it becomes hundreds or thousands of lines of code dealing with calling external binaries, streams and proper error handling. Perhaps if you're only dealing with text processing it will work, but the moment you start piping together external programs via Python it's all pointless.

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Glad I'm not the only one. Honestly, whenever bash comes up in any context, 10 different people feel compelled to express this whole replace all bash scripts with python sentiment and I just have no clue what the fuck they're talking about.

I would consider myself an expert or at least near-expert in python, but I don't see opportunities to replace my shell scripts with python popping up left and right. Do you open files manually and set up pipe chains with subprocess.Popen? I've done this, and its generally many more LOC compared to the shell original, and harder to read.

On the other hand, I'd consider myself maybe 7/10 skill level with bash, but most developers are only ever a 2/10 or 3/10 with bash/shell. I can't help but think that the average developer's lack of shell understanding is where all these suggestions to convert to python come from. If it's that easy or beneficial to convert to python, then it probably should have been written in python originally.

I think when you have a very-well-written bash script, it starts to get pretty close to python in size, but python wins in readability. A well written bash script will handle errors cleanly, will not die on quoting problems, and can use complex data structures or objects when data handling gets hairy.

When you use regexes, letting python use them directly seems to be much cleaner than quoting and passing them to awk/sed/grep or other text processing tools.

Additionally, python seems to have libraries to handle all kinds of input like json and csv.

One thing that python doesn't do as naturally as bash is invoke commands. For python I usually include some functions to run commands passed as a list, and check the return code or return the output. then 'cmd -f $arg1' becomes myrun('cmd','-f', arg1)

Stringing up a pipe with a mix of awk, tr, sed, cut, sort, uniq etc. is certainly not more readable than a Python script with comments not invoking any of these but using Python's data structures, or even data frames/SQL.

100% agree. There are some libraries like https://amoffat.github.io/sh/ that aim to make that easier, but they always have some quirks that, funnily enough, are often the corner cases you were hitting in your complicated Bash script in the first place.

sh is the secret to transliterating bash to python. It's basically bash with proper loops and variables and string operations.

    import sh
    names = sh.ls("./src")
    for name in names:
        sh.mv(["./src/" + name, "./dst/" + name + ".out"])

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