Version 0.4 (2012-10-15)

  • ~2000 changes, numerous bugfixes

  • Syntax

    • All keywords are now strict and may not be used as identifiers anywhere
    • Keyword removal: 'again', 'import', 'check', 'new', 'owned', 'send', 'of', 'with', 'to', 'class'.
    • Classes are replaced with simpler structs
    • Explicit method self types
    • ret became return and alt became match
    • import is now use; use is now extern mod`
    • extern mod { ... } is now extern { ... }
    • use mod is the recommended way to import modules
    • pub and priv replace deprecated export lists
    • The syntax of match pattern arms now uses fat arrow (=>)
    • main no longer accepts an args vector; use os::args instead

  • Semantics

    • Trait implementations are now coherent, ala Haskell typeclasses
    • Trait methods may be static
    • Argument modes are deprecated
    • Borrowed pointers are much more mature and recommended for use
    • Strings and vectors in the static region are stored in constant memory
    • Typestate was removed
    • Resolution rewritten to be more reliable
    • Support for 'dual-mode' data structures (freezing and thawing)

  • Libraries

    • Most binary operators can now be overloaded via the traits in `core::ops'
    • std::net::url for representing URLs
    • Sendable hash maps in core::send_map
    • `core::task' gained a (currently unsafe) task-local storage API

  • Concurrency

    • An efficient new intertask communication primitive called the pipe, along with a number of higher-level channel types, in core::pipes
    • std::arc, an atomically reference counted, immutable, shared memory type
    • std::sync, various exotic synchronization tools based on arcs and pipes
    • Futures are now based on pipes and sendable
    • More robust linked task failure
    • Improved task builder API

  • Other

    • Improved error reporting
    • Preliminary JIT support
    • Preliminary work on precise GC
    • Extensive architectural improvements to rustc
    • Begun a transition away from buggy C++-based reflection (shape) code to Rust-based (visitor) code
    • All hash functions and tables converted to secure, randomized SipHash