Working With Nightly

Table of Contents

Why?

  • Dependencies may require nightly

  • Compile times and error messages are sometimes better (sometimes not)

  • There are several features which are not yet stable

  • Compiler plugins

Using Nightly

Use rustup to override the version used in a specific directory.

cd /nightly_project
rustup override set nightly

Features

Features are gated behind "Feature Flags" which are enabled project wide.

Some examples:

  • asm which provides inline assembly support

  • no_std which disables implict extern crate std

  • inclusive_range, similar to the stable exclusive_range

Enabling Features

To enable a feature, add the following line into src/main.rs (for executables), or`src/lib.rs` (for libraries):

#![feature(asm, no_std)]

Compiler Plugins

Compiler Plugins add additional capabilities to Rust. For example:

  • (Previously) custom derive

  • Linters

  • Libraries like regex_macros

Enabling Compiler Plugins

To enable a compiler plugin add the following line into src/main.rs (for executables), or`src/lib.rs` (for libraries):

#![plugin(some_plugin)]

Warning

It is unknown, when and if ever compiler-plugins will be stabilised.

Stable development on nightly

It is recommendable to use a nighly compiler close to the release version used.