> the tool isn't really set up to accommodate a momentarily-invalid state.

I've struggled to explain to students, teachers and others my frustrations with anything that isn't plaintext code. This is it - thank you!

I think it's also a neat learning concept about why it's important one is _able_ to make mistakes when writing code. So many are overwhelmed by the flexibility or fragility of syntaxes but there's actually a lot of power in that.