alt Hacker NewsWhenever people look for "better shell scripting", they always run into the second-system effect. Trying to shove everything that wasn't in the first system, into the second system.
Bash shell scripting is already close to perfect for what it is intended. Where people always complain is one of three areas: 1) "footguns", 2) "not enough features", 3) "not a programming language", 4) inexperience.
1) is almost entirely due to it being a programming-like language bolted onto an interactive console terminal. Bash has a lot of changes over vanilla Bourne/Posix that make it less console-y and more programming-y. But if you take away the interactive-terminal-ness itself, then you don't need most of the Bashisms.
2) is almost always a mistake. Bash has pretty much all the features you need. But again, it's hampered by the interactive-terminal-ness; take that away, and you can do pretty much anything, with ease.
3) is because programmers don't understand what scripts are for. They are not for writing robust programs. They are for solving a small problem, in a specific, tailored way, with the least amount of effort and time. This means that you should be abandoning all of the programmer's best practices and rules. Throw out safety, reliability, consistency, verifiability, etc. What you end up with is a solution that works, with nothing extra.
4) comes when people simply don't know how to use Bash very well, which is 90% of the time. Ever since I became a programmer two decades ago, the great unwashed masses of techno-dweebs who call themselves "programmers" have been picking up complex and nuanced technology that they have never bother to formally learn, and then complain that it sucks and they need an alternative. When in reality, the problem is almost always either a) they didn't read the manual, b) they haven't practiced using it, or c) they're using the wrong tool anyway.
Doesn't matter if you disagree with me. We will be using the same shell scripts in 20 years. Know why? Because you can't make it any simpler, and it just works. Complain all you want about it not being perfect. You simply will not be able to make something better without simultaneously making it worse. Its killer feature is its lack of features and design. It is the anti-programming language. And boy do I love it.
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#4 is the big one for me.
And I don't really care. I'm super comfortable with one-liners in my bash shell. I can do useful stuff in bash scripts, but typically with a base script gets to more than a dozen or so lines, I find myself way more productive rewriting it in Python instead. Not because Python is "better" or because bash is "worse", but because _I'm_ better with Python and _I'm_ worse with bash. And I don't feel any urgent need to get better at bash, because the work I do means I pretty much always have Python available (at least everywhere I have bash available).
I know bash is way more capable than my kindergarten-grade use of it. And it'll remain in my toolkit and crontab for as long as unix-like OSen exist. But I'll be very unlikely to ever keep writing a bash script past a dozen or two lines ever again.
On 4, my favorite example is hearing "do I quote this?" when trying to explain something. It's such a simple question, but quotes don't delimit strings like they do in other programming languages, they do something else entirely, so getting into it really reveals they have almost no clue how the language works.
> Ever since I became a programmer two decades ago, the great unwashed masses of techno-dweebs who call themselves "programmers" have been picking up complex and nuanced technology that they have never bother to formally learn, and then complain that it sucks and they need an alternative. When in reality, the problem is almost always either a) they didn't read the manual, b) they haven't practiced using it
This kind of Dunning-Kruger-esque arrogance in software is intensely aggravating to me. Nobody presumes that you can master, say, a musical instrument, without intensive practice over a timespan of years; yet for some reason people can get plopped out the other end of a bootcamp and suddenly identify as world class programmers in 16 weeks without the requisite thousands of hours of practice with hands on keyboard, reading the manual, studying how the computer works, and actually solving technical problems.
well said!
"Bash shell scripting is already close to perfect for what it is intended."
It is very difficult to write a parser for any derivative of the POSIX shell. The lex/yacc utilities cannot be used; the lexer and parser must exchange state.
It would be better if the shell was an LR-parsed language with a yacc grammar. The yacc utility is itself in POSIX.2.
Here is a talk about an OCaml implementation of a parser for the POSIX shell:
https://archive.fosdem.org/2018/schedule/event/code_parsing_...
Here is another talk about an Ada parser implementation:
https://archive.fosdem.org/2019/schedule/event/ada_shell/
The language grammar is unfortunate.