I remember one being posted on here a while back, but I'd be open to any shell that's meant to be programmed.

The Dilemma: It's easy to start writing bash commands idly to do simple things, but when you want to wrap functionality into a library or program, bash is terrible and unmaintainable.

A shell language is designed to allow you to execute commands one-by-one on the command line and see their results easily. It's useful for small scripts, but anything large become unwieldy quickly.

A programming language allows you to create large readable and maintainable libraries. But using programming languages as an interactive shell is tough, while the functionality is all there, it's tough to access, and doesn't have the luxuries of autocomplete and other features, and the syntax isn't forgiving.

A shell language that is meant for programming would combine the best of these two and allow a programmer to just spin up a shell and test stuff and eventually wrap all of the shell commands they had tested out into a library.

Does anyone know of any languages like this? Established, or in-development?