A programming language that inspired me, but never really took off was https://www.magpie-lang.org. It was heavily based on pattern matching and supported multi-methods. It's creator, Bob Nystrom, as far as I know now works on Dart language. https://journal.stuffwithstuff.com

Love the "this" patterns + multimethods I had a language built on pattern matching, and now one on prototypal OO, and this feels like an obvious (in hindsight) missed opportunity. Thanks for sharing.

If you're talking about making constructors using pattern matching, yeah I think that is brilliant.

I mean the "Left to Right Arguments"

I remember reading about Magpie way back when. He also wrote the Wren language, which looks fun for different reasons.