Feature suggestion: Code round-tripping

The blockly interface is amazing. However, one thing that makes it feel very different from the existing PXT experience is the absence of round-tripping.

I found a paper on round-tripping by one of the blockpy contributors here, in case it is of any use to you for future developments:

https://groups.google.com/forum/#!topic/blockly/kzq_g-jF98c