es - extensible shellEs is an extensible shell. The language was derived from the Plan 9 shell, rc, and was influenced by functional programming languages, such as Scheme, and the Tcl embeddable programming language. This implementation is derived from Byron Rakitzis's implementation of rc, and was written by Paul Haahr & Byron Rakitzis. Why? Es is an extensible Unix shell with first class functions, lexical scope, ex
