[Pre-RFC] Extended dot operator (as possible syntax for `await` chaining)

[scottmcm]

@160R

Meanwhile: would it be a good idea to adopt it for closures to simplify things like |x|x.to_string() ?

Some previous discussion on this topic:

Simple partial application

Some of these partial application syntax proposals are approaching https://www.boost.org/libs/lambda, which added lambdas to C++ as a library. For example, one could do _1 * 2 for what rust calls |x| x * 2. I suspect nightly Rust could do something similar today. (Nightly to be able to implement the Fn* traits.) The biggest problem that has is figuring out the extent of the lambda: How does one decide if foo().bar(_) is |x| foo().bar(x) or match foo() { t => |x| t.bar(x) }? (Not unlike th…