PXT Team's experience with +/- mutators in Blockly?


I’m working on an extension for Blockly that adds +/- mutators, similar to the ones MakeCode uses (although they are closer to the OpenRoberta mutators at the moment).

I’m trying to figure out what the best design for these blocks would be:

  • Is it better to have a single minus for the whole block? Or a minus for each input?
  • Is it better to have separate “if - else if” and “if - else if - else” blocks? Or should you be able to add the else via mutation (like MakeCode allows)?

I was wondering if you guys had ever studied/focus grouped your mutator UI. Or if you had any other insights about the design.

Thank you for your time! I really appreciate any advice you can give me!

P.S: You can view the blockly-forums discussion here.