The Edition Guide

Introduction

What are editions?

• What are editions?
  • Creating a new project
  • Transitioning an existing project to a new edition

Rust 2015

• Rust 2015

Rust 2018

• Rust 2018
  • 2018-Specific Changes
  • Module system
    • Raw identifiers
    • Path clarity
    • More visibility modifiers
    • Nested imports with use
  • Error handling and panics
    • The ? operator for easier error handling
    • ? in main and tests
    • Controlling panics with std::panic
    • Aborting on panic
  • Control flow
    • Loops can break with a value
    • async/await for easier concurrency
  • Trait system
    • impl Trait for returning complex types with ease
    • dyn Trait for trait objects
    • More container types support trait objects
    • Associated constants
    • No more anonymous parameters
  • Slice patterns
  • Ownership and lifetimes
    • Non-lexical lifetimes
    • Default match bindings
    • '_, the anonymous lifetime
    • Lifetime elision in impl
    • T: 'a inference in structs
    • Simpler lifetimes in static and const
  • Data types
    • Field init shorthand
    • ..= for inclusive ranges
    • 128 bit integers
    • “Operator-equals” are now implementable
    • union for an unsafe form of enum
    • Choosing alignment with the repr attribute
  • SIMD for faster computing
  • Macros
    • Custom Derive
    • Macro changes
    • At most one repetition
  • The compiler
    • Improved error messages
    • Incremental Compilation for faster compiles
    • An attribute for deprecation
  • Rustup for managing Rust versions
  • Cargo and crates.io
    • cargo check for faster checking
    • cargo install for easy installation of tools
    • cargo new defaults to a binary project
    • cargo rustc for passing arbitrary flags to rustc
    • Cargo workspaces for multi-package projects
    • Multi-file examples
    • Replacing dependencies with patch
    • Cargo can use a local registry replacement
    • Crates.io disallows wildcard dependencies
  • Documentation
    • New editions of the “the book”
    • The Rust Bookshelf
    • The Rustonomicon
    • Full documentation for std::os
  • rustdoc
    • Documentation tests can now compile-fail
    • Rustdoc uses CommonMark
  • Platform and target support
    • libcore for low-level Rust
    • WebAssembly support
    • Global allocators
    • MSVC toolchain support
    • MUSL support for fully static binaries
    • cdylib crates for C interoperability

The Next Edition

• The Next Edition
  • Next-Specific Changes
  • The dbg! macro
  • No jemalloc by default
  • Uniform Paths
  • literal macro matcher
  • ? operator in macros
  • const fn
  • Pinning