Unix shells are already a bit LISP-y on a superficial level, because commands are syntactically like impure functions in prefix notation. Subshells act a lot like parens in a LISP, and the pipeline itself has analogs in FP like Clojure's thread macro. And of course, the command line itself is a REPL.
Elvish visibly leans into this to try to have a consistent syntax. Sometimes the similarities go deeper, too; IIRC, its number types are inspired by Scheme, for example.
> Elvish visibly leans into this to try to have a consistent syntax. Sometimes the similarities go deeper, too; IIRC, its number types are inspired by Scheme, for example.
Yes! Similarity to Lisp is very much a deliberate design choice and I feel happy every time a Lisper picks that up :)
I believe Elvish has also contributed a novel solution to the Lisp-1/Lisp-2 divide by making the space of command names equivalent to the subspace of variable names with a suffix - the command "foo" is equivalent to the variable "$foo~" and vice versa. (There's a bit more twist than that - the command "foo" can also resolve to the external command named "foo", but then that's represented by the "$e:foo~" variable.)
Powershell is closer to FP than OOP. What people mean is that it supports structured data.
Powershell is not true FP, but, if you stretch terminology:
- the unit of feature delivery is the function
- you can pass functions as values (but it's not idiomatic or elegant)
- objects tend to look more like anonymous records than OOP classes with methods
- pattern matching is supported (sort of)
Elvish visibly leans into this to try to have a consistent syntax. Sometimes the similarities go deeper, too; IIRC, its number types are inspired by Scheme, for example.