Just `mut` alongside `let mut`

nvijayap:

I am talking about the future - an enhancement to make the code elegant.

The core problem is that you're also, perhaps unknowingly, asking for

• a giant argument about when it's better to use which form
• a giant argument about whether everyone should have to move to the new form
• a giant argument about how rustfmt should decide which to use
• a bunch of confusion when people see older resources that weren't updated
• a ton of churn on everyone with existing code to move to the new thing

It's just not worth it.

The rust philosophy for this is that it's fine to ask people to just accept the structured suggestion. I, for example, continually make the mistake of struct Foo { x: u32; y: u32 } -- a semicolon instead of a comma -- but the answer isn't "Rust should accept that"; it's "oops, I accepted the structured suggestion and it's fine now".