[nightski]

We have not invented a language that is immune to technical debt or leaky abstractions. Haskell's type system is not rich enough to let us impose all the constraints implied by the mathematics.

However it is a significant improvement on allowing one to express the constraints in the type system preventing large classes of bugs and towards providing proper abstractions.

Let's not throw the baby out with the bathwater. No one is claiming FP developers are "better" than OO developers. In fact why would anyone ever classify themselves as one or the other? Instead we should use the best tools for the job.