Why Why Functional Programming Matters Matters

Pareto and Cost/Benefit! A Type System is just a set of features in the compiler and other programming tools. Does our field have good data on the cost-benefit of features in type systems? Granted, this is quite complicated. Additional type data can enable features, like more kinds of and more reliable automated refactorings, but it can also incur costs, like slowing down the writing of new code and the programming tools.

Due to the Pareto principle, I suspect that most of the benefit of both dynamic language environments and type systems come from a minority of the features in each. I also suspect that many of the costs vary with context and time-frame. "Programming in the Large" problems may never, ever apply to certain projects. Long term maintenance issues may not apply to other projects.

"Experiments" in programming language design generally seem to be at a ridiculously large granularity with ridiculously poor experimental design. (Let's write a new language!) Is it any wonder then, that our "field" is really "half a field?"