> The bugs I have are very rarely related with the type of a variable. They are incomplete/incorrect implementations of business rules. The type system doesn't solve that.
It doesn't until you encode the business rules in the type system. But in a well-designed language that's actually fairly easy.
> The other point of the article is that dynamic typing makes code rot. I am not convinced that static languages do any better. Code rot is not a problem of the typing system, it's a problem with the programmer writing the code, or the environment he's in. Let's see what happens when he inherits a 5-year-old Haskell codebase.
Having done both, it's far easier to port an old statically-typed codebase to newer versions of its dependencies than to do the same for an old dynamically-typed codebase. Compare a Wicket upgrade (seamlessly smooth, and the compiler will catch anything you've missed) with a Rails/Django upgrade (batten down the hatches, hope you've got high test coverage, and even then you'll likely have something break).
It doesn't until you encode the business rules in the type system. But in a well-designed language that's actually fairly easy.
> The other point of the article is that dynamic typing makes code rot. I am not convinced that static languages do any better. Code rot is not a problem of the typing system, it's a problem with the programmer writing the code, or the environment he's in. Let's see what happens when he inherits a 5-year-old Haskell codebase.
Having done both, it's far easier to port an old statically-typed codebase to newer versions of its dependencies than to do the same for an old dynamically-typed codebase. Compare a Wicket upgrade (seamlessly smooth, and the compiler will catch anything you've missed) with a Rails/Django upgrade (batten down the hatches, hope you've got high test coverage, and even then you'll likely have something break).