New format! syntax has rough edges

[H2CO3]

@scouten

While we like this new syntax, we're finding it limiting that it can only reference existing variables and not any form of expression.

So, although the new Clippy warning nudges us toward a shorter syntax and team-wide consistency in formatting how we print variables, it nudges us toward inconsistency overall because we can't use that same form for other expressions.

Is this on the radar of the Rust language team?

Note that this is very intentional. Putting arbitrary expressions in strings is not a good thing, it's confusing and way too much complexity to be worth the (perceived) advantages.

(This came up previously, and I said pretty much the same thing back then.)