|« April 2015|
Ted writes: "Look, guys, at the end of the day, if Rails is about Ruby and the things that a scripting language can do that a compiled, statically-typed language can’t, then Rails definitely has a place in the world and I’ll take the time to learn it." My position is that that’s precisely what Rails is about. Sure, some of the lessons that Rails teaches can be carried across to statically-typed languages just fine, but some of the most important ones simply won’t translate. Rails is a testament to the power of dynamic languages in general, and of Ruby in particular.
Here’s one example: it’s a mistake Ted did make in his first blog, and it’s a mistake others make as well. "I mean, I see a bunch of intelligent code-generation," Ted wrote, and if you’re coming from a static language background it’s easy to look at Rails’ scaffolding support and default views and think that’s what you’re seeing. I thought so, too. If that’s what the scaffolds are, they aren’t too impressive — partly because that’s easy to do, but mostly because generated code like that eventually becomes a burden. Most of us have seen code generation tools before, and they’re great for getting started, but when you move beyond what the generated code will do for you you’re in a world of hurt, often having to throw away what’s built into the framework and supply your own versions of everything.
But Rails isn’t doing "intelligent code-generation" — unless what you mean by that is that it’s doing the least possible code generation. Crack open those scaffolds and look inside. They’re almost empty! Usually they’re just trivial class definitions, with no methods or fields. All of the behavior comes at runtime, through inherited reflective logic. Rails is generating structure, not behavior, and that turns out to be a huge win. Ruby makes that possible, partly through its rich support for runtime reflection, but mostly because its dynamic, open nature makes it a breeze to fill in those empty spaces incrementally, overriding and extending little by little the default behavior that’s built into the framework.
And that’s just one example of how a dynamic language makes Rails possible, and why some of Rails’ goodness is easy for we static-language types to miss at first glance.
What’s Rails about?