Command line parsing was the first task performed by most applications back in the 80’s and even today it is very important. Yet after all these years there isn’t a standard parser available .NET, leaving developers to reinvent this common pattern over and over again.
In the current CTP, it appeared as thought .NET 4 would include a command line parser. We were going to report on this and the comparison to Mono’s API for the same task, but it turns out it was mistakenly released.
We are not shipping System.Shell.CommandLine in .NET 4. This was based on an intern project from a couple of years back that was mistakenly public in the .NET Framework 4.0 CTP. It wasn't a design that we were happy with and has been removed and will not be present in the next preview release.
We have a *much better* command line parsing API, along the lines of Mono.Options, that we're planning to release on CodePlex later this year.
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