Ah, Sather gets mentioned. That's a name I haven't heard in a long time. I remember looking at it during the latter half of the 90s when I was searching for the perfect OO language...
Sather was something I was first exposed to at university in the mid 90s, and I still have a lot of respect for its looping mechanism. Code inclusion in classes rather than inheritance was also pretty cool. Pre/post conditions, invariants. I miss a lot of it.
I recently revisited it for Advent of Code (where part of the challenge was getting the compiler itself to even build with even semi-modern tooling), and a lot of the above features still have value.
https://www1.icsi.berkeley.edu/~sather/