Extend argument for supporting Guid values

[delfuria]

I tried to extend the library for supporting Guid values.
I have created a GuidArgumentAttribute and a GuidArgument classes following this link
https://github.com/j-maly/CommandLineParser/wiki/Extensibility-&-custom-arguments
but i cannot reach to execute because i get a MissingMethodException.
What has been wrong ?
Thanks

[j-maly]

Since Guid was not one of the types supported out of the box by ValueArgument, you would need to override this method:
public virtual TValue Convert(string stringValue)

But now I've added Guid to ValueArgument directly as you suggested.

[delfuria]

Thanks a lot.