I am a big fan of DI, but you can often get a lot of useful unit testing done when you try and keep I/O mostly seperate from the rest of the code. If you have e

I am a big fan of DI, but you can often get a lot of useful unit testing done when you try and keep I/O mostly seperate from the rest of the code. If you have ever programmed in Haskell you will know what I mean.