Now and then I get to deal with development groups who have built their software systems using a language like Ruby or PHP. Many of them are proud of their exte

Now and then I get to deal with development groups who have built their software systems using a language like Ruby or PHP. Many of them are proud of their extensive automated tests. They'll brag about how they have 45,000 or more unit tests, for instance. Yet when we actually look at these tests, many of them just end up implementing a half-baked type system. Even if they don't realize it, or don't want to acknowledge it, users of dynamic languages do want strong, static typing. It is one of the most useful tools there is when it comes to helping detect or avoid various problems. Rather than doing it in a sensible matter, by letting the computer (via a compiler, for example) efficiently do the hard or tedious work, they just choose to do it themselves manually.