Stabilize used Rust features #331
Description
To be able to build it with a stable Rust version:
#![feature(box_patterns)]
#![feature(box_syntax)]
#![feature(slice_patterns)]
#![feature(try_trait)]
#![feature(custom_attribute)]{{ message }}
To be able to build it with a stable Rust version:
#![feature(box_patterns)]
#![feature(box_syntax)]
#![feature(slice_patterns)]
#![feature(try_trait)]
#![feature(custom_attribute)]