Here's an interesting thought. All built-in types in D default initialize to the closest thing that they have to an error. Floating points arguably do the best job of this with NAN, and integral types arguably the worst with 0, but that is, as I understand it, the basic idea: default initializations initialize to an error value (or as close to one as you can get). That way, it quickly becomes obvious when you failed to properly initialize one before using it. So, the question is this: what about structs?
Structs default initialize to whatever their member variables are directly initialized to. That may or may not be an error state, but I don't get the impression that people generally _try_ and make it an error state. What should be the best practice on this? Should we generally _try_ and make struct initializers initialize to error states, just like the primitive types do - with the idea that you really are supposed to initialize them or assign to them before you use them. Or should we treat structs differently and try and make their default states something other than an error state? By no means am I claiming that we should _always_ try and make a struct's init property an error or _always_ make it valid (that's going to depend on what exactly the struct is for and what it does), but which would be the best practice in the general case? - Jonathan M Davis