C# requires that every method be in some class, even if it is a static method in a static class in the global namespace. Other languages allow "top level" functions. A recent stackoverflow post asks why that is. I am asked "why doesn't C# implement...

Since LINQ was announced I've seen a lot of really positive feedback and a lot of questions and concerns. Keep 'em coming! We need this feedback so that we can both correct misconceptions early and get the design right now. One of the misconceptions...

The other day someone asked me about a slightly odd but very useful feature in JScript.NET, and I figure if one person asks me about it, maybe more people want to know as well. In JScript.NET you can say class alpha { var foo; class bravo { function...

One more thing -- I said earlier that the VBScript float-to-string algorithm was a little bit different than the JScript algorithm. We can demonstrate quite easily by comparing the outputs of two nigh-identical programs: ' VBScript print 9.2 * 100.0 <...

I went to Joel Spolsky's geek dinner at Crossroads the other night, which was a lot of fun. I didn't get much of a chance to chat with Joel, as he was surrounded by a cadre of adoring fans three deep the whole time. I mostly hung out with KC and Larry...

Before I get going, a couple notable milestones. First, this is post number 200 ! Who would have believed that I'd have so much to ramble on about? ("Anyone who knows you" would be the correct answer to that rhetorical question I suppose.) ...

Before I begin today's technical topic, a quick link to what promises to be a terrifying , I mean, terribly interesting blog. Mario , the guy who tests the code that I write and thereby keeps me honest, the guy who's application for a backyard barbecue...

Last time I gave some vague, high-level definitions of the type system concepts promotable , assignable and coercible . Today I'll give a more precise definition of promotable . The others I'll define more precisely later. Suppose we have an assignment...

Stan Lippman has started an interesting series of blog entries on how Managed C++ determines which function foo to call when you call foo(bar) given that there may be several visible functions of that name in the current scope. That's quite coincidental...

I am totally amused that the comments on yesterday's entry are nigh-isomorphic to the argument that we had over this in October 2000. As noted, f.bar(f); does in fact call the base class function, not the derived class function as some might expect. ...

When you're designing a new programming language, the "main line" cases are easy. It's the "corner" cases that bedevil language designers -- the little fiddly bits where two language features that make perfect sense on their own interact in some weird...

You learn something new every day in this job. Or, more accurately, some days you learn things again that you'd forgotten years ago. Someone just asked me why it is that all JScript .NET classes are serializable. I admit it, my first reaction...

Recall that in Part One we discussed eval on the client, and in Part Two we discussed eval on the server. Today, I answer a question about eval in JScript .NET. S omeone sent me mail the other day asking why this C# program snippet didn't work: ...

Hey, I'm back! And in my new location. That was the longest and least relaxing vacation I've ever taken. Fun, yes. Relaxing, no. And to top it off, my kitchen is not done yet. We're shooting for being able to run water tonight and actually use appliances...

What happens when you assign a hard-typed CLR array to a variable annotated with a different CLR array type?...

As I mentioned earlier, when you try to use a JScript .NET array when a CLR array is expected, we create a copy. But when you go the other way, things are a little different. Rather than producing a copy, using a CLR array as a JScript .NET array "wraps it up". No copy is made. The operation is therefore efficient and preserves identity. Changes made to a wrapped array are preserved...

JScript .NET arrays and hard-typed CLR arrays work together, but because these two kinds of arrays are so different they do not work together perfectly. The problem is essentially that JScript .NET arrays are much more dynamic than CLR arrays. JScript .NET arrays can change size, can have elements of any type, and so on. ...

As I was saying the other day, CLR arrays and JScript arrays are totally different beasts. It is hard to imagine two things being so different and yet both called the same thing. Why did the CLR designers and the JScript designers start with the same desire -- create an array system -- and come up with completely different implementations? ...

JScript arrays are sparse, variable-sized, single-dimensional, soft-typed associative arrays. CLR arrays are the opposite in every way! They are dense, fixed-size, multi-dimensional, hard-typed nonassociative arrays. It is hard to imagine two more different data structures with the same name. Making them interoperate at all was a pain in the rear, believe me. ...

I thought I might spend a few days talking about the JScript and JScript .NET type systems, starting with some introductory material. There is a lot of terminology associated with type systems. What exactly is weak typing? What is a subtype? Just what is a type anyway? These terms are often bandied about and seldom actually defined precisely.

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I just realized that on my list of features missing from JScript.NET "fast mode" I forgot about the caller property of functions....

The other day I noted that extending the built-in objects in JScript .NET is no longer legal in "fast mode". Of course, this is still legal in "compatibility mode" if you need it, but why did we take it out of fast mode?...

My entry the other day about fast mode in JScript .NET sparked a number of questions which deserve fuller explanations. I’ll try to get to them in my next couple of blog entries. For example, when I said that it was no longer legal to redefine a function, I wasn’t really clear on what I meant. ...

Earlier I mentioned that two of the design goals for JScript .NET were high performance and compatibility with JScript Classic . Unfortunately these are somewhat contradictory goals! JScript Classic has many dynamic features which make generation...

I hate octal. Octal causes bugs. I hate bugs, particularly stupid "gotcha" bugs....