> Why not? If I'm writing scripts for automating configuration on modern macOS, for example, where ZSH is installed by default, why not write ZSH scripts?

I guess there are two reasons

- if the script doesn't need arrays, POSIX sh (dash) scripts will be much faster than bash/zsh scripts

- if you do need arrays, bash is vastly more ubiquitous than any other shell on the planet right now (except POSIX sh). It's installed on almost all Linux distributions by default. I'm not gonna use a ZSH script because I'd have to install ZSH, which seems unnecessary. A good example is tomb, which is a ZSH script for encryption on Linux.

If you're sure that your scripts will always run on macOS, use POSIX sh if you don't need arrays and ZSH if you do need them.

Good advice, thank you..

It's more "why not write scripts?" Actually making use of a shell's control structures is code smell until we have far better shells than we currently do. They're optimized for user interaction, not necessarily anything else.

If you're gonna be calling a lot of external programs and interacting with files a lot, non-shell scripting languages tend to feel pretty clunky.

I know what you mean, though. Most shell languages don't feel like flexible, expressive programming languages in the way that they ought to and could.

As you may know, there are some new shells/languages that are trying to bridge the gap in a way that still leaves the shell well-suited to interactive use. The Oil shell wiki has a great list of them (and Oil is one such shell itself, of course): https://github.com/oilshell/oil/wiki/Alternative-Shells

> If you're gonna be calling a lot of external programs and interacting with files a lot, non-shell scripting languages tend to feel pretty clunky.

Perl's actually pretty good here; I'm pretty new to it, but it's generally what I reach for when I feel like a bash script has gotten just a bit too complicated.

Perl definitely is the sweet spot. Even then, I think python with multiprocessing and the pipe class is better than bash in some circumstances.

If all you're doing is `a | b | c | d` then use bash but if you're pulling stuff out of the middle in a loop, yeah, might want to use a real language.