"Replace" is a loaded word, this is blogspam. In Catalina the default login shell for new users will be Zsh, but Bash will still be on the system (and likely still the default shell for upgraded users). So in practice, if your bangs are correct and you upgrade your systems, nothing will change.
"Apple replaces shell designed 30 years ago with one designed 29 years ago"
FISH, the "Friendly Interactive Shell"-- now 15 years old-- provides a more substantial leap forward in autocompletion and auto-suggestion, while adding some breaking changes to improve the overall design of the language and user experience. It's still highly compatible with bash or zsh syntax for day-to-day usage.
Try `fish_config` to launch a browser where you can select a theme. Enjoy autocompletion for 500 commands by default. Need help for a built-in command? Try `help test` to read the docs for the `test` command in your browser.
Oh my zsh and a few zsh plugings completely blow fish out of the water for me. First off zsh doesn't have any supposed syntax improvements so I can take any new skills I acquire to environments other than my own.
I think array indexes start at 1 in zsh rather than 0 as they do in bash. It sounds like such a ludicrous change that I'm having trouble recalling if this is really true, but I had previously used zsh a lot... Just got lazy with my last MBP upgrade and never installed zsh.
Most shell scripts start with a reference to the program that should execute them at the top of the file (i.e. #!/usr/bin/bash), so this shouldn't affect most people, especially since this change will only apply to new users.
Depends on the default Zsh configuration file they provide. When I used Zsh in the past with just the default config I found some Bash 'features' missing. Stuff like reverse-i-search (ctrl-r) and tab-completion. Most of them are simple config changes but they don't make a default Zsh a drop-in replacement for Bash from a user perspective. I think this is also the reason projects like Oh-my-zsh.
No, because the syntax of zsh is mostly similar to bash. Yes, because it's only mostly similar. For scripts that start with `#!/bin/bash`, no difference at all, because they will still run with bash.
If you just type commands into a prompt, then no, not really. If you do anything more advanced than that I think you’ll notice the differences quite quickly (I did).
On my laptop, which is my only macOS device, the only scripts I use are a few python ones. Anything more advanced is on a linux desktop or server. Otherwise, on mac it's mostly ranger, vim, and ssh.
I've been tempted to try other shells, but at this point after using Bash for 15 years or something, I've just never had the motivation enough to do it.
