c639a78dc4
This is an implementation of a map and set for integer keys. It's an ordered container (by byte order, which is sorted order for integers and byte strings when done in the right direction) with O(1) worst-case lookup, removal and insertion. There's no rebalancing or rehashing so it's actually O(1) without amortizing any costs.
The fanout can be adjusted in multiples of 2 from 2-ary through 256-ary, but it's hardcoded at 16-ary because there isn't a way to expose that in the type system yet. To keep things simple, it also only allows `uint` keys, but later I'll expand it to all the built-in integer types and byte arrays.
There's quite a bit of room for performance improvement, along with the boost that will come with dropping the headers on `Owned` `~` and getting rid of the overhead from the stack switches to the allocator. It currently does suffix compression for a single node and then splits into two n-ary trie nodes, which could be replaced with an array for at least 4-8 suffixes before splitting it. There's also the option of doing path compression, which may be a good or a bad idea and depends a lot on the data stored.
I want to share the test suite with the other maps so that's why I haven't duplicated all of the existing integer key tests in this file. I'll send in another pull request to deal with that.
Current benchmark numbers against the other map types:
TreeMap:
Sequential integers:
insert: 0.798295
search: 0.188931
remove: 0.435923
Random integers:
insert: 1.557661
search: 0.758325
remove: 1.720527
LinearMap:
Sequential integers:
insert: 0.272338
search: 0.141179
remove: 0.190273
Random integers:
insert: 0.293588
search: 0.162677
remove: 0.206142
TrieMap:
Sequential integers:
insert: 0.0901
search: 0.012223
remove: 0.084139
Random integers:
insert: 0.392719
search: 0.261632
remove: 0.470401
@graydon is using an earlier version of this for the garbage collection implementation, so that's why I added this to libcore. I left out the `next` and `prev` methods *for now* because I just wanted the essentials first.
The Rust Programming Language
This is a compiler for Rust, including standard libraries, tools and documentation.
Installation
The Rust compiler currently must be built from a tarball, unless you are on Windows, in which case using the installer is recommended.
Since the Rust compiler is written in Rust, it must be built by a precompiled "snapshot" version of itself (made in an earlier state of development). As such, source builds require a connection to the Internet, to fetch snapshots, and an OS that can execute the available snapshot binaries.
Snapshot binaries are currently built and tested on several platforms:
- Windows (7, Server 2008 R2), x86 only
- Linux (various distributions), x86 and x86-64
- OSX 10.6 ("Snow Leopard") or greater, x86 and x86-64
You may find that other platforms work, but these are our "tier 1" supported build environments that are most likely to work.
Note: Windows users should read the detailed getting started notes on the wiki. Even when using the binary installer the Windows build requires a MinGW installation, the precise details of which are not discussed here.
To build from source you will also need the following prerequisite packages:
- g++ 4.4 or clang++ 3.x
- python 2.6 or later (but not 3.x)
- perl 5.0 or later
- gnu make 3.81 or later
- curl
Assuming you're on a relatively modern *nix system and have met the prerequisites, something along these lines should work.
$ curl -O http://static.rust-lang.org/dist/rust-0.5.tar.gz
$ tar -xzf rust-0.5.tar.gz
$ cd rust-0.5
$ ./configure
$ make && make install
You may need to use sudo make install if you do not normally have
permission to modify the destination directory. The install locations
can be adjusted by passing a --prefix argument to
configure. Various other options are also supported, pass --help
for more information on them.
When complete, make install will place several programs into
/usr/local/bin: rustc, the Rust compiler; rustdoc, the
API-documentation tool, and rustpkg, the Rust package manager and build system.
License
Rust is primarily distributed under the terms of both the MIT license and the Apache License (Version 2.0), with portions covered by various BSD-like licenses.
See LICENSE-APACHE, LICENSE-MIT, and COPYRIGHT for details.
More help
The tutorial is a good starting point.