alt Hacker NewsWhile using "monads" in functional languages is a neat trick, I do not like them.
In my opinion, the concept of automaton is fundamental and it deserves equal standing with the concept of function (even if it is a higher level concept that is built upon that of function).
I believe that functional programming is preferable wherever it is naturally applicable, and most programs have components of this kind, but most complete application programs, i.e. which do input and output actions, are automata, not functions and it is better to not attempt to masquerade this with tricks that provide no benefits.
Therefore, I prefer a programming language that has a pure functional subset, allowing the use of that subset where desirable, but which also has standard imperative features (e.g. assignment), to be used where appropriate.
You can't just put assignment in a functional language though - you lose the ability to fearlessly refactor that's the whole point. You either need something like a stratified language (which I've never seen actually implemented, much less production-ready, as much as I like the design of Noether), or you use, well, monads.