SatherSather is an object-oriented programming language. It has been developed at Berkeley's ICSI, reached a good level of maturity and is currently part of the GNU project. The language is reminiscent of Eiffel but is contravariant, with a very clever syntax. It has anonymous functions, iterators, abstract classes, generics. The current implementation of the compiler is written in Sather and emits C code, which leads to various compiling inconveniences. The standarad library is rich enough, but lacks interfaces to the most commonly used libraries.
For the language-collectors, it will taste a little bit like a compiled Ruby. Most activity around the language has ceased. Sadly.
Original things that might be worth considering as inspiration for a new language: iterators, operators as syntactic sugar, implicit declarations,...
This page is linked from: Design by Contract