I'm writing a shell that does this; right now I'm working on the language itself (a somewhat functional language with basic types and records) and its parser (t

I'm writing a shell that does this; right now I'm working on the language itself (a somewhat functional language with basic types and records) and its parser (the syntax is like a terser OCaml mixed with Ruby, designed to be quick to write), but eventually it'll reimplement most unix programs so that their output is actually a type it recognizes, and it'll have something like a FCI (Foreign Command Interface) that would let you easily parse the ouput of commands it doesn't implement. It's not uploaded anywhere yet (and there's not much to look at right now, just an unfinished parser and the beginning of an interpreter), but when I have time to work on it and put it in a somewhat functional state I'll post it on here too.