`pub fn needs_par_as_let_scrutinee(order: i8) -> bool`

## Expand description

Suppose we have `let _ = e`

and the `order`

of `e`

.
Is the `order`

such that `e`

in `let _ = e`

needs parentheses when it is on the RHS?

Conversely, suppose that we have `(let _ = a) OP b`

and `order`

is that of `OP`

.
Can we print this as `let _ = a OP b`

?