Provide interfaces and test files via stdinput

[buksy90]

I have a file that defines various interfaces and I have another library that outputs javascript code as string. I need to check that the code output from the library is compliant with the interfaces defined.

It would be best if I wouldn't have to save the output to files and then check. Is there a way to provide both interfaces and code to test as parameters when running tsd?
If not, is it something that could be easily added and could be implemented in future?

[tommy-mitchell]

See #196 for discussion on this.