Await syntax summary

summary.txt

A hopefully complete list of all proposed syntaxes:
  await!(fut)
  await fut
    await? fut
    await fut?
  await(fut)
  await{ fut }
  fut await
  fut.await
    maybe with prefix `await fut` through unified macro
    and `val.match`
  fut(await)
  fut.await()
  fut.await!()
    maybe with prefix `await fut` through unified macro
  fut#
  fut@
  fut$
  fut!
  fut@await
  fut...
  fut~
  <--fut 
    (not quite sure what exactly)
  go fut
  fut->
  |> fut
  fut.[it]
    `it` being a keyword refering to an implicit argument to `[]` block
  fut^^
  fut>>>

A not quite arbitrary selection of relevant comparison posts:
<https://aturon.github.io/2018/04/24/async-borrowing/> On why postfix is not about combinators
<https://github.com/rust-lang/rust/issues/57640#issuecomment-455361619> future of result vs. result of future
<https://github.com/rust-lang/rust/issues/57640#issuecomment-455749122> chaining visibility comparison
<https://github.com/rust-lang/rust/issues/57640#issuecomment-455763530> extended comparison table
<https://github.com/rust-lang/rust/issues/57640#issuecomment-455836523> comparison on reqwest use case
<https://github.com/rust-lang/rust/issues/57640#issuecomment-455846086> real world example transformation await!() to pre/postfix
<https://github.com/rust-lang/rust/issues/57640#issuecomment-456625030> links to arguments for/against prefix/postfix/macro
<https://github.com/rust-lang/rust/issues/57640#issuecomment-456672228> list of goals and evaluation summary
<https://github.com/rust-lang/rust/issues/57640#issuecomment-457101180> prosa summary of postfix vs. prefix
<https://github.com/rust-lang/rust/issues/57640#issuecomment-457457727> prefix survey in C# code and Rust comparison
<https://github.com/rust-lang/rust/issues/57640#issuecomment-457503195> specific sigil vs postfix comparison
<https://github.com/rust-lang/rust/issues/57640#issuecomment-457976527> reminder to focus semantic, not only syntactic, differences
<https://github.com/rust-lang/rust/issues/57640#issuecomment-458022676> chaining appears seldomly used in async code currently
<https://github.com/rust-lang/rust/issues/57640#issuecomment-461679267> summary&response to criticisms of postfix @