[sillycross]

I agree that it's very important to clearly communicate the designs to the users. However, I feel that it's practically hard for many reasons. For example, it's hard to argue in the document why something is not done (e.g. why are entities referenced by pointer instead of string name). And also keep in mind that the document is read by people of various degrees of expertise. It's hard to make all of them happy.

In fact, when I first started using LLVM, I created a basic block and put everything into it. Then LLVM complains, and I learnt that a basic block must be a list of straight-lined operations followed by a branch. At that moment I was feeling similar to the author in this post: "Why is there such a bizzare rule that makes me harder to write my program?" But after I was forced to rewrite my code to conform with this rule, surprisingly, I found my program logic much easier to understand. And when I gradually knew a bit more about LLVM, I understood that the basic block rule is there for other very good reasons as well.

So is this good design? Clearly it is. This design decision not only helps with the library itself, but also forces the users to write code in a less error-prone way.

However, is it possible to justify this in the document, so another user won't have to go through my initial frustration? I am doubtful. At least my personal feeling is that, I won't be able to understand why it is designed this way, unless I actually have played around and experienced it myself.

I hope this clarifies my point on why sometimes it is hard to communicate design philosophies.