The function trait section reminded me about effect systems and Purescripts row polymorphism[0], which is a great little way to be able to encode properties of

The function trait section reminded me about effect systems and Purescripts row polymorphism[0], which is a great little way to be able to encode properties of your functions. I think Rust might quickly run into the “negative trait” problem trying to get that working, while embracing an effect system like Purescripts might get you the goods in a “principled” way. Though I haven’t thought about this deeply. [0]: https://rtpg.co/2016/07/20/supercharged-types.html https://rtpg.co/2016/07/20/supercharged-types.html