rust/RELEASES.txt

Version 0.7 (July 2013)
-----------------------

   * ~2000 changes, numerous bugfixes

   * Language
      * `impl`s no longer accept a visibility qualifier. Put them on methods
        instead.
      * The borrow checker has been rewritten with flow-sensitivity, fixing
        many bugs and inconveniences.
      * The `self` parameter no longer implicitly means `&'self self`,
        and can be explicitly marked with a lifetime.
      * Overloadable compound operators (`+=`, etc.) have been temporarily
        removed due to bugs.
      * The `for` loop protocol now requires `for`-iterators to return `bool`
        so they compose better.
      * The `Durable` trait is replaced with the `'static` bounds.
      * Trait default methods work more often.
      * Structs with the `#[packed]` attribute have byte alignment and
        no padding between fields.
      * Type parameters bound by `Copy` must now be copied explicitly with
        the `copy` keyword.
      * It is now illegal to move out of a dereferenced unsafe pointer.
      * `Option<~T>` is now represented as a nullable pointer.
      * `@mut` does dynamic borrow checks correctly.
      * The `main` function is only detected at the topmost level of the crate.
        The `#[main]` attribute is still valid anywhere.
      * Struct fields may no longer be mutable. Use inherited mutability.
      * The `#[no_send]` attribute makes a type that would otherwise be
        `Send`, not.
      * The `#[no_freeze]` attribute makes a type that would otherwise be
        `Freeze`, not.
      * Unbounded recursion will abort the process after reaching the limit
        specified by the `RUST_MAX_STACK` environment variable (default: 1GB).
      * The `vecs_implicitly_copyable` lint mode has been removed. Vectors
        are never implicitly copyable.
      * `#[static_assert]` makes compile-time assertions about static bools.
      * At long last, 'argument modes' no longer exist.
      * The rarely used `use mod` statement no longer exists.

   * Syntax extensions
      * `fail!` and `assert!` accept `~str`, `&'static str` or `fmt!`-style
        argument list.
      * `Encodable`, `Decodable`, `Ord`, `TotalOrd`, `TotalEq`, `DeepClone`,
        `Rand`, `Zero` and `ToStr` can all be automatically derived with
        `#[deriving(...)]`.
      * The `bytes!` macro returns a vector of bytes for string, u8, char,
        and unsuffixed integer literals.

   * Libraries
      * The `core` crate was renamed to `std`.
      * The `std` crate was renamed to `extra`.
      * More and improved documentation.
      * std: `iterator` module for external iterator objects.
      * Many old-style (internal, higher-order function) iterators replaced by
        implementations of `Iterator`.
      * std: Many old internal vector and string iterators,
        incl. `any`, `all`. removed.
      * std: The `finalize` method of `Drop` renamed to `drop`.
      * std: The prelude no longer reexports any modules, only types and traits.
      * std: Prelude additions: `print`, `println`, `FromStr`, `ApproxEq`, `Equiv`,
        `Iterator`, `IteratorUtil`, many numeric traits, many tuple traits.
      * std: New numeric traits: `Fractional`, `Real`, `RealExt`, `Integer`, `Ratio`,
        `Algebraic`, `Trigonometric`, `Exponential`, `Primitive`.
      * std: Tuple traits and accessors defined for up to 12-tuples, e.g.
        `(0, 1, 2).n2()` or `(0, 1, 2).n2_ref()`.
      * std: Many types implement `Clone`.
      * std: `path` type renamed to `Path`.
      * std: `mut` module and `Mut` type removed.
      * std: Many standalone functions removed in favor of methods and iterators
        in `vec`, `str`. In the future methods will also work as functions.
      * std: `reinterpret_cast` removed. Use `transmute`.
      * std: ascii string handling in `std::ascii`.
      * std: `Rand` is implemented for ~/@.
      * std: `run` module for spawning processes overhauled.
      * std: Various atomic types added to `unstable::atomic`.
      * std: Various types implement `Zero`.
      * std: `LinearMap` and `LinearSet` renamed to `HashMap` and `HashSet`.
      * std: Borrowed pointer functions moved from `ptr` to `borrow`.
      * std: Added `os::mkdir_recursive`.
      * std: Added `os::glob` function performs filesystems globs.
      * std: `FuzzyEq` renamed to `ApproxEq`.
      * std: `Map` now defines `pop` and `swap` methods.
      * std: `Cell` constructors converted to static methods.
      * extra: `rc` module adds the reference counted pointers, `Rc` and `RcMut`.
      * extra: `flate` module moved from `std` to `extra`.
      * extra: `fileinput` module for iterating over a series of files.
      * extra: `Complex` number type and `complex` module.
      * extra: `Rational` number type and `rational` module.
      * extra: `BigInt`, `BigUint` implement numeric and comparison traits.
      * extra: `term` uses terminfo now, is more correct.
      * extra: `arc` functions converted to methods.
      * extra: Implementation of fixed output size variations of SHA-2.

   * Tooling
      * `unused_variable`  lint mode for unused variables (default: warn).
      * `unused_unsafe` lint mode for detecting unnecessary `unsafe` blocks
        (default: warn).
      * `unused_mut` lint mode for identifying unused `mut` qualifiers
        (default: warn).
      * `dead_assignment` lint mode for unread variables (default: warn).
      * `unnecessary_allocation` lint mode detects some heap allocations that are
        immediately borrowed so could be written without allocating (default: warn).
      * `missing_doc` lint mode (default: allow).
      * `unreachable_code` lint mode (default: warn).
      * The `rusti` command has been rewritten and a number of bugs addressed.
      * rustc outputs in color on more terminals.
      * rustc accepts a `--link-args` flag to pass arguments to the linker.
      * rustc accepts a `-Z print-link-args` flag for debugging linkage.
      * Compiling with `-g` will make the binary record information about
        dynamic borrowcheck failures for debugging.
      * rustdoc has a nicer stylesheet.
      * Various improvements to rustdoc.
      * Improvements to rustpkg (see the detailed release notes).

Version 0.6 (April 2013)
------------------------

   * ~2100 changes, numerous bugfixes

   * Syntax changes
      * The self type parameter in traits is now spelled `Self`
      * The `self` parameter in trait and impl methods must now be explicitly
        named (for example: `fn f(&self) { }`). Implicit self is deprecated.
      * Static methods no longer require the `static` keyword and instead
        are distinguished by the lack of a `self` parameter
      * Replaced the `Durable` trait with the `'static` lifetime
      * The old closure type syntax with the trailing sigil has been
        removed in favor of the more consistent leading sigil
      * `super` is a keyword, and may be prefixed to paths
      * Trait bounds are separated with `+` instead of whitespace
      * Traits are implemented with `impl Trait for Type`
        instead of `impl Type: Trait`
      * Lifetime syntax is now `&'l foo` instead of `&l/foo`
      * The `export` keyword has finally been removed
      * The `move` keyword has been removed (see "Semantic changes")
      * The interior mutability qualifier on vectors, `[mut T]`, has been
        removed. Use `&mut [T]`, etc.
      * `mut` is no longer valid in `~mut T`. Use inherited mutability
      * `fail` is no longer a keyword. Use `fail!()`
      * `assert` is no longer a keyword. Use `assert!()`
      * `log` is no longer a keyword. use `debug!`, etc.
      * 1-tuples may be represented as `(T,)`
      * Struct fields may no longer be `mut`. Use inherited mutability,
        `@mut T`, `core::mut` or `core::cell`
      * `extern mod { ... }` is no longer valid syntax for foreign
        function modules. Use extern blocks: `extern { ... }`
      * Newtype enums removed. Use tuple-structs.
      * Trait implementations no longer support visibility modifiers
      * Pattern matching over vectors improved and expanded
      * `const` renamed to `static` to correspond to lifetime name,
        and make room for future `static mut` unsafe mutable globals.
      * Replaced `#[deriving_eq]` with `#[deriving(Eq)]`, etc.
      * `Clone` implementations can be automatically generated with
        `#[deriving(Clone)]`
      * Casts to traits must use a pointer sigil, e.g. `@foo as @Bar`
        instead of `foo as Bar`.
      * Fixed length vector types are now written as `[int, .. 3]`
        instead of `[int * 3]`.
      * Fixed length vector types can express the length as a constant
        expression. (ex: `[int, .. GL_BUFFER_SIZE - 2]`)

   * Semantic changes
      * Types with owned pointers or custom destructors move by default,
        eliminating the `move` keyword
      * All foreign functions are considered unsafe
      * &mut is now unaliasable
      * Writes to borrowed @mut pointers are prevented dynamically
      * () has size 0
      * The name of the main function can be customized using #[main]
      * The default type of an inferred closure is &fn instead of @fn
      * `use` statements may no longer be "chained" - they cannot import
        identifiers imported by previous `use` statements
      * `use` statements are crate relative, importing from the "top"
        of the crate by default. Paths may be prefixed with `super::`
        or `self::` to change the search behavior.
      * Method visibility is inherited from the implementation declaration
      * Structural records have been removed
      * Many more types can be used in static items, including enums
        'static-lifetime pointers and vectors
      * Pattern matching over vectors improved and expanded
      * Typechecking of closure types has been overhauled to
        improve inference and eliminate unsoundness
      * Macros leave scope at the end of modules, unless that module is
        tagged with #[macro_escape]

   * Libraries
      * Added big integers to `std::bigint`
      * Removed `core::oldcomm` module
      * Added pipe-based `core::comm` module
      * Numeric traits have been reorganized under `core::num`
      * `vec::slice` finally returns a slice
      * `debug!` and friends don't require a format string, e.g. `debug!(Foo)`
      * Containers reorganized around traits in `core::container`
      * `core::dvec` removed, `~[T]` is a drop-in replacement
      * `core::send_map` renamed to `core::hashmap`
      * `std::map` removed; replaced with `core::hashmap`
      * `std::treemap` reimplemented as an owned balanced tree
      * `std::deque` and `std::smallintmap` reimplemented as owned containers
      * `core::trie` added as a fast ordered map for integer keys
      * Set types added to `core::hashmap`, `core::trie` and `std::treemap`
      * `Ord` split into `Ord` and `TotalOrd`. `Ord` is still used to
        overload the comparison operators, whereas `TotalOrd` is used
        by certain container types

   * Other
      * Replaced the 'cargo' package manager with 'rustpkg'
      * Added all-purpose 'rust' tool
      * `rustc --test` now supports benchmarks with the `#[bench]` attribute
      * rustc now *attempts* to offer spelling suggestions
      * Improved support for ARM and Android
      * Preliminary MIPS backend
      * Improved foreign function ABI implementation for x86, x86_64
      * Various memory usage improvements
      * Rust code may be embedded in foreign code under limited circumstances
      * Inline assembler supported by new asm!() syntax extension.

Version 0.5 (December 2012)
---------------------------

   * ~900 changes, numerous bugfixes

   * Syntax changes
      * Removed `<-` move operator
      * Completed the transition from the `#fmt` extension syntax to `fmt!`
      * Removed old fixed length vector syntax - `[T]/N`
      * New token-based quasi-quoters, `quote_tokens!`, `quote_expr!`, etc.
      * Macros may now expand to items and statements
      * `a.b()` is always parsed as a method call, never as a field projection
      * `Eq` and `IterBytes` implementations can be automatically generated
        with `#[deriving_eq]` and `#[deriving_iter_bytes]` respectively
      * Removed the special crate language for `.rc` files
      * Function arguments may consist of any irrefutable pattern

   * Semantic changes
      * `&` and `~` pointers may point to objects
      * Tuple structs - `struct Foo(Bar, Baz)`. Will replace newtype enums.
      * Enum variants may be structs
      * Destructors can be added to all nominal types with the Drop trait
      * Structs and nullary enum variants may be constants
      * Values that cannot be implicitly copied are now automatically moved
        without writing `move` explicitly
      * `&T` may now be coerced to `*T`
      * Coercions happen in `let` statements as well as function calls
      * `use` statements now take crate-relative paths
      * The module and type namespaces have been merged so that static
        method names can be resolved under the trait in which they are
        declared

   * Improved support for language features
      * Trait inheritance works in many scenarios
      * More support for explicit self arguments in methods - `self`, `&self`
        `@self`, and `~self` all generally work as expected
      * Static methods work in more situations
      * Experimental: Traits may declare default methods for the implementations
        to use

   * Libraries
      * New condition handling system in `core::condition`
      * Timsort added to `std::sort`
      * New priority queue, `std::priority_queue`
      * Pipes for serializable types, `std::flatpipes'
      * Serialization overhauled to be trait-based
      * Expanded `getopts` definitions
      * Moved futures to `std`
      * More functions are pure now
      * `core::comm` renamed to `oldcomm`. Still deprecated
      * `rustdoc` and `cargo` are libraries now

   * Misc
      * Added a preliminary REPL, `rusti`
      * License changed from MIT to dual MIT/APL2

Version 0.4 (October 2012)
--------------------------

   * ~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

Version 0.3  (July 2012)
------------------------

   * ~1900 changes, numerous bugfixes

   * New coding conveniences
      * Integer-literal suffix inference
      * Per-item control over warnings, errors
      * #[cfg(windows)] and #[cfg(unix)] attributes
      * Documentation comments
      * More compact closure syntax
      * 'do' expressions for treating higher-order functions as
        control structures
      * *-patterns (wildcard extended to all constructor fields)

   * Semantic cleanup
      * Name resolution pass and exhaustiveness checker rewritten
      * Region pointers and borrow checking supersede alias
        analysis
      * Init-ness checking is now provided by a region-based liveness
        pass instead of the typestate pass; same for last-use analysis
      * Extensive work on region pointers

   * Experimental new language features
      * Slices and fixed-size, interior-allocated vectors
      * #!-comments for lang versioning, shell execution
      * Destructors and iface implementation for classes;
        type-parameterized classes and class methods
      * 'const' type kind for types that can be used to implement
        shared-memory concurrency patterns

   * Type reflection

   * Removal of various obsolete features
      * Keywords: 'be', 'prove', 'syntax', 'note', 'mutable', 'bind',
                 'crust', 'native' (now 'extern'), 'cont' (now 'again')

      * Constructs: do-while loops ('do' repurposed), fn binding,
                    resources (replaced by destructors)

   * Compiler reorganization
      * Syntax-layer of compiler split into separate crate
      * Clang (from LLVM project) integrated into build
      * Typechecker split into sub-modules

   * New library code
      * New time functions
      * Extension methods for many built-in types
      * Arc: atomic-refcount read-only / exclusive-use shared cells
      * Par: parallel map and search routines
      * Extensive work on libuv interface
      * Much vector code moved to libraries
      * Syntax extensions: #line, #col, #file, #mod, #stringify,
        #include, #include_str, #include_bin

   * Tool improvements
      * Cargo automatically resolves dependencies

Version 0.2  (March 2012)
-------------------------

   * >1500 changes, numerous bugfixes

   * New docs and doc tooling

   * New port: FreeBSD x86_64

   * Compilation model enhancements
      * Generics now specialized, multiply instantiated
      * Functions now inlined across separate crates

   * Scheduling, stack and threading fixes
      * Noticeably improved message-passing performance
      * Explicit schedulers
      * Callbacks from C
      * Helgrind clean

   * Experimental new language features
      * Operator overloading
      * Region pointers
      * Classes

   * Various language extensions
      * C-callback function types: 'crust fn ...'
      * Infinite-loop construct: 'loop { ... }'
      * Shorten 'mutable' to 'mut'
      * Required mutable-local qualifier: 'let mut ...'
      * Basic glob-exporting: 'export foo::*;'
      * Alt now exhaustive, 'alt check' for runtime-checked
      * Block-function form of 'for' loop, with 'break' and 'ret'.

   * New library code
      * AST quasi-quote syntax extension
      * Revived libuv interface
      * New modules: core::{future, iter}, std::arena
      * Merged per-platform std::{os*, fs*} to core::{libc, os}
      * Extensive cleanup, regularization in libstd, libcore

Version 0.1  (January 2012)
---------------------------

   * Most language features work, including:
      * Unique pointers, unique closures, move semantics
      * Interface-constrained generics
      * Static interface dispatch
      * Stack growth
      * Multithread task scheduling
      * Typestate predicates
      * Failure unwinding, destructors
      * Pattern matching and destructuring assignment
      * Lightweight block-lambda syntax
      * Preliminary macro-by-example

   * Compiler works with the following configurations:
      * Linux: x86 and x86_64 hosts and targets
      * MacOS: x86 and x86_64 hosts and targets
      * Windows: x86 hosts and targets

   * Cross compilation / multi-target configuration supported.

   * Preliminary API-documentation and package-management tools included.

Known issues:

   * Documentation is incomplete.

   * Performance is below intended target.

   * Standard library APIs are subject to extensive change, reorganization.

   * Language-level versioning is not yet operational - future code will
     break unexpectedly.