What kind of errrors do you think are not caught with static typing? Usually people who say this aren't familiar with languages that have type classes...
Citing awj's post above:
"Some of the biggest errors are subtle failures in the implementation of business logic."
Other examples:
- bumping into unkonwn bugs of a library you are calling - implementation of an external (library) function behaving differently than the documentation - various memory leak problems - locking issues - race conditions
etc
Static typing can prevent errors in business logic.
>various memory leak problems - locking issues - race conditions
All are bugs that static typing has had tremendous success in preventing. Have you any experience in a HM like type system?
Please do elaborate, it could be a great post.
But If you mean to say that locking issues can be prevented because you can apply STM (software transactional memory) by using suitable Monads, then, well, i can also have STM in a dynamic language, even applying it by wrapping code in an "atomic" context (i.e. see the STMX library for Common Lisp) so the statements contained within are performed atomically (and thus guaranteed to work or either roll-back.)
As for memory leaks, Haskell (if that's the HM language you had in mind) automatically manages memory, so I would guess this isn't a problem at all. However, automatic management memory management is orthogonal to "static vs dynamically typed".
Thus, i'm curious, and yes, i don't have enough experience with HM-type languages, which should be the way to go if one wants to use static typing...
How can you roll back failed transactions without explicitly typed effects?
It helps a bit that most clojure datastructures are immutable/persistant by default.