I have yet to find a proper replacement for bash. Especially for scripts.
The two most common alternatives are 1) using some of the newer shells people have created, like Oil shell [0], or 2) using programming language like Python, JavaScript, or PHP.
The problem with using a newer shell is that you'll have to install the new shell anywhere you want to use the script. Meanwhile bash is ubiquitous. Unless you're the only one maintaining the script, you're requiring others to learn the other shell to maintain the script.
The problem with using another programming language is that they rarely have good ergonomics for doing what bash does: stringing together commands, command input, command output, and files. If you try to do that in another programming language, things suddenly get a lot more complicate or at least more verbose.
So I still use bash, but I recognize that it's strength is in running other commands and dealing with I/O. If I'm doing complicated logic that doesn't involve that, then I'll offload my work to another language. Sometimes that just means calling a python script from bash, not avoiding bash completely.
If people found that they work better by taking other approaches, the please share them.
I'll still write bash, but only if it's very trivial (~ <= 10-ish lines, no super-complex conditionals, etc). For anything else, it's worth stepping up to just about any more-robust language. If you don't like the hoops that something like Python makes you go through for basic shell-like operations, maybe try Perl? For middling-complexity scripts, perl can be a nice win over bash, without all the development overhead of Python. Perl5 is pretty much installed everywhere and universally compatible for anything but the very latest language features.
I usually resort to running inline scripts using python3 or node (using only the standard library) if I need to do something that I can't express in bash easily. That means avoiding stuff that have to look up and I won't remember or be able to debug in a month.
I like the idea of running inline scripts. This means that all the logic is in a single file so you don't have multiple files to copy around (e.g. a .sh file and a .py file).
I've done this with awk and jq, but haven't done it with node or python. But why not? It sounds like a good approach for some cases.
I love bash for anything that doesn't need to scale. The reason is reliability. I can't tell you how many times I've run into problems with python or similar on small library implementations. If I need to make an http request in my code and I'm using curl in bash and something fails, I can pretty much guarantee the problem is not curl itself. It's battle tested and deterministic. However the python script that forgets to wrap a try catch or configure proper tls auth or some other quirk? I have had those eat hours/days of my time and having to resort to tcpdump to sort out what's really happening. Same with SQL libraries/ORM vs SQL cli, same with Json/xml parsing libraries vs jq etc.
> The problem with using another programming language is that they rarely have good ergonomics for doing what bash does: stringing together commands, command input, command output, and files. If you try to do that in another programming language, things suddenly get a lot more complicate or at least more verbose.
tclsh is one way around that. Use a real first-class programming language, but in a mode where calling programs is as easy as it is in shell.
The two most common alternatives are 1) using some of the newer shells people have created, like Oil shell [0], or 2) using programming language like Python, JavaScript, or PHP.
The problem with using a newer shell is that you'll have to install the new shell anywhere you want to use the script. Meanwhile bash is ubiquitous. Unless you're the only one maintaining the script, you're requiring others to learn the other shell to maintain the script.
The problem with using another programming language is that they rarely have good ergonomics for doing what bash does: stringing together commands, command input, command output, and files. If you try to do that in another programming language, things suddenly get a lot more complicate or at least more verbose.
So I still use bash, but I recognize that it's strength is in running other commands and dealing with I/O. If I'm doing complicated logic that doesn't involve that, then I'll offload my work to another language. Sometimes that just means calling a python script from bash, not avoiding bash completely.
If people found that they work better by taking other approaches, the please share them.
[0] https://www.oilshell.org