Would this be good for someone to learn coding on?

I've been using this machine as a web development purposes and some app development using Xcode, and I can tell you that learning coding (nothing heavy) will be perfectly fine on rMB.

 

Glad that I can help
You can always return it and get a rMBP (as this may be even more appealing with redesign & USB C update) so it's a win win for you!

 

I'm working with Python and mySQL (and Maya) and it works very, very well for this.
But as beginner, most of your learning projects will be small, regardless of language, and the rMB should have no problems handling it.

The only thing I wouldn't do with it is learning how to develop games like in Unity 3D or Unreal 4 (e.g. using Blueprints). But even that it may handle if complexity is low.

 

No. The screen is way too small.
Spaces helps but is hindered by performance on the RMB.

 

Depending on what is meant by "coding" you can learn plenty on a raspberry pi.