During this time, the potential value of static type systems has become quite clear to me. For the most part I still really don’t care about protecting programmers from their own mistakes. Instead what I value is the ability to make promises about program behavior that untrusting parties can verify on their own (for non-hackish metaprogramming and secure code distribution), the ability to write expressive abstractions that don’t sacrifice any run-time performance, and the ability to infer a program’s implementation from its interface. I still like the dynamic programming ideal of putting lots of power in the programmer’s hands… but whence else comes this power? Rather than stubbornly reinventing the existing static type research under some other name, I embrace it.
I haven’t felt the pain of the asynchronous callback nesting problem firsthand, but I know a horror close to that one: Monadic programming in Groovy. Observe the indentation.
In fact, that indentation-heavy part of the Blade code is what originally got me fed up with using Groovy and interested in making Penknife as an intermediate project on the way to Blade. Well, my work on Penknife has been so focused on modularity and hygiene that it’s slack on what really matters: Syntax. Oh, syntax, how you really really matter so! :-p