[pornel]

• try!() has been replaced by ?. You don't even need to know — the compiler will tell you.

• futures 0.1 has been replaced with std::futures.

This is it. This is the exhaustive list of A->B feature changes in the last 42 releases of Rust. Now you know them all.

Rust is aggressive with keeping everyone using the current stable release. In C++ you may need to keep track of feature history to know if something is too new or too old for your compiler/project. There's no such thing in Rust. If you know a feature exists, you can use it.