Introduction to Code Contracts [Melitta Andersen]

Relacja z C2C (Communities to Communities) 2009

. jak .NET by Maciej Aniserowicz — Mon, 16 Mar 2009 02:00:35 GMT

Relacja z C2C (Communities to Communities) 2009

. jak .NET by Maciej Aniserowicz — Mon, 16 Mar 2009 01:59:14 GMT

Dzień: 14 marca 2009. Miejsce: Wydział Biologii UW. Wydarzenie: druga edycja konferencji Communities

Preview of Code Contract Tools Now Available

CLR Team Blog — Wed, 04 Mar 2009 23:06:25 GMT

We’ve mentioned Code Contracts over on the BCL Blog a few times now, but never yet on the CLR Blog. Basically,

Preview of Code Contract Tools Now Available [Melitta Andersen]

BCL Team Blog — Tue, 24 Feb 2009 02:02:52 GMT

In my Introduction to Code Contracts post, I mentioned that the tools to enable runtime checking and

re: Introduction to Code Contracts [Melitta Andersen]

Flavien Charlon — Mon, 01 Dec 2008 19:11:10 GMT

Hi,

Contracts are really nice.

In order to be able to use them properly though, we will need pre and postconditions from all the classes we use in our program, for exemple, List<T>.Count is always positive or zero.

Are you going to update the whole BCL with code contracts for .NET 4.0? This sounds like a huge work, but without that, contracts won't be usable at their full potential.

My second question is why C# wouldn't have a syntax that would get translated into CodeContracts upon compilation.

With this we get a good langage support in C#, as well as the ability to have it supported accross all CLR langages.

契約によるプログラミング.NET

biac のそれさえもおそらくは幸せな日々@nifty — Tue, 25 Nov 2008 18:08:46 GMT

InfoQ に日本語記事が載ったので f(^^; .NET 4 の新機能を探る：コード契約作者 Jonathan Allen, 翻訳者金森諭投稿日 2008年11月22日午前12時53分契約による設計は静的型付けのように、コンパイル時に検証されないと一定の動作を実行することができないという考え方だ。契約

Various Links

Mike Taulty's Blog — Thu, 20 Nov 2008 23:02:35 GMT

I've been catching up on my blog reading...interesting stuff I came across; PNRP in Windows 7 being...

re: Introduction to Code Contracts [Melitta Andersen]

int19h — Sun, 16 Nov 2008 12:24:30 GMT

Judging by its past track, one .NET language that will almost certainly provide syntactic sugar for the library contracts is Delphi Prism (aka RemObjects Oxygene). They do in fact already have "require", "ensure", and "invariant" keywords, so it would make sense for them to plug them into those BCL bits for .NET 4.0, and extend the syntax to cover all other cases ("require ... on raise ..." etc).

re: Introduction to Code Contracts [Melitta Andersen]

Steven the .NET Junkie — Sat, 15 Nov 2008 16:57:04 GMT

I don't like using attributes for the contracts. It’s almost impossible to do compile time checking on them, and they’re very verbose. I've seen Spec# and it has the ideal language syntax. I hope this syntax makes it to C# 5.0. (Well… I'm really hoping C# 4.0 will have all this, but I know this isn't going to happen ;-)).

re: Introduction to Code Contracts [Melitta Andersen]

BCL Team — Sat, 15 Nov 2008 02:27:34 GMT

Hi Judah,

Thanks for pointing out that I neglected to mention how code contracts work on interfaces. As you've said, you can't put code into interface methods. What you do is create a separate class to contain the contracts that <i>explicitly</i> implements the interface. Then you link them with a pair of attributes: [ContractClass(Type)] and [ContractClassFor(Type)]. For example you could have an interface IFoo with a class IFooContract that contains the contracts.

[ContractClass(typeof(IFooContract))]

interface IFoo

{

int DoSomething(string parameter);

}

[ContractClassFor(typeof(IFoo))]

sealed class IFooContract : IFoo

{

int IFoo.DoSomething(string parameter)

{

CodeContract.Requires(parameter != null);

CodeContract.Ensures(0 <= CodeContract.Result<int>());

throw new NotImplementedException("This method is only for interface contracts. Do not call");

}

As for your question about attributes, if they were powerful enough, we certainly would have considered using them to implement contracts, though I can't say for sure what we would have decided. As it is, we don't know of any plans for more expressive attributes, and even if they do come along later, we would already have an established contracts system. There would by that point be many factors to take into consideration when looking at adding attribute support.

Thanks,

Melitta