On Wednesday evening I received a great phone call on my cell phone while at home. It was Don Box. I've known Don since about 1995, from when we used to speak at the same technical conferences, he about COM, me about CORBA. He is an all-around great guy.
Don called to take issue with something I wrote about COM IDL in a recent blog entry. Specifically, he took me to task for this:
First, the article claims that, with IDL, "there is always a conceptual association between an interface and an in-memory representation of an object." While this is true of COM IDL, it's wholly and completely wrong with respect to CORBA.
Don wondered if I was trying to take a dig at COM IDL. I can definitely say that that wasn't my intent. What I was trying to do was guess which IDL the authors of the "WSDL vs. IDL" article were thinking of when they said that IDLs imply in-memory object representations. I thought of COM only because of its use of vtables for object dispatch, but as Don correctly pointed out, the vtable choice is independent of COM IDL. In re-reading what I wrote, I see that I could have worded it better to avoid making it seem like a contentious half-truth. Thanks, Don, for pointing this out to me.
Don also said that he felt that in pointing out that ASP.NET allows you to directly map methods on programming language classes into web services operations, I made it seem like it's the only toolkit that does that. Again, that wasn't my intent. I chose that one only because I felt most people would be familiar with it. Lots of web services toolkits, especially the early ones, have provided features that help directly expose programming language artifacts as web services. The main reason for this is expediency -- it helps developers get services up and running quickly with minimal fuss. While I maintain that such exposure is the wrong way to do things, it doesn't do any good to sit on a high horse about it, because people are going to do it no matter what. If a customer asks for such a feature, you give it to them, because if you instead lecture them that this isn't the right way to do things, they'll simply take their business elsewhere.
Anyway, Don, thanks for the constructive feedback. I hope this clarifies things. It certainly was good to hear from you.