On December 6, 2018, a very important version of the Rust language, its compiler, and its standard library was released: stable version 1.31. This version has been defined as the 2018 edition, meaning it is a milestone that will be used as a reference for the years to come.
Before this, there was another version, 1.0, which was defined as the 2015 edition. This edition was characterized by the word stability. Up until version 1.0, every version of the compiler applied breaking changes to the language or to the standard library, forcing the developers to apply sweeping changes to their code base. From version 1.0, efforts have been made to ensure that any future version of the compiler can correctly compile any code written for version 1.0 or successive versions. This is called backward compatibility.
However, many features were applied to the language and to the standard library before the release of the 2018 edition. Many new libraries used...
