[giornogiovanna]

Yeah, I don't know why Prelude.head doesn't return a Maybe. Anyway, the point stands.

• In Java forgetting to check for null will crash your program.

• In C, forgetting to check for NULL will lead to undefined behavior.

• In Haskell, you either have to (a) check for Nothing, or (b) explicitly say "crash the program if this is Nothing" by using a function like fromJust or head, which internally does (a). This is always an improvement over C, and often an improvement over Java.

Side note: I like Rust's convention of consistently naming these might-crash-your-program methods "unwrap" and "expect".

[pdexter]

Yeah I think rust has better defaults here.

[crimsonalucard]

I get the choice. It's unintuitive for basic types to be wrapped in a maybe mondad. People expect addition, subtraction and division to return numbers. To have division be the only operation to return an optional is a bit off.

I get the choice of why it wasn't done with haskell even though I disagree with it.