Interesting but not always correct. Eg: slide 64 encourages the reader to "Using sum vs inheritance", and then goes on to show the "good" algebraic datatypes (

Interesting but not always correct. Eg: slide 64 encourages the reader to "Using sum vs inheritance", and then goes on to show the "good" algebraic datatypes (no behaviour, just data) vs the "bad"... multiple class implementing the same interface (which I wouldn't call inheritance).