auto merge of #12650 : huonw/rust/librand, r=alexcrichton

Move std::rand to a separate rand crate

This functionality is not super-core and so doesn't need to be included
in std. It's possible that std may need rand (it does a little bit now,
for io::test) in which case the functionality required could be moved to
a secret hidden module and reexposed by librand.

Unfortunately, using #[deprecated] here is hard: there's too much to
mock to make it feasible, since we have to ensure that programs still
typecheck to reach the linting phase.

Also, deprecates/removes `rand::rng` (this time using `#[deprecated]`), since it's too easy to accidentally use inside a loop, making things very slow (have to read randomness from the OS and seed the RNG each time.)

Author: bors

mk/crates.mk

@@ -50,14 +50,14 @@
 ################################################################################
 
 TARGET_CRATES := std extra green rustuv native flate arena glob term semver \
-                 uuid serialize sync getopts collections num test time
+                 uuid serialize sync getopts collections num test time rand
 HOST_CRATES := syntax rustc rustdoc fourcc hexfloat
 CRATES := $(TARGET_CRATES) $(HOST_CRATES)
 TOOLS := compiletest rustdoc rustc
 
 DEPS_std := native:rustrt native:compiler-rt
-DEPS_extra := std term sync serialize getopts collections time
-DEPS_green := std native:context_switch
+DEPS_extra := std term sync serialize getopts collections time rand
+DEPS_green := std rand native:context_switch
 DEPS_rustuv := std native:uv native:uv_support
 DEPS_native := std
 DEPS_syntax := std term serialize collections
@@ -71,15 +71,16 @@ DEPS_glob := std
 DEPS_serialize := std collections
 DEPS_term := std collections
 DEPS_semver := std
-DEPS_uuid := std serialize
+DEPS_uuid := std serialize rand
 DEPS_sync := std
 DEPS_getopts := std
-DEPS_collections := std
+DEPS_collections := std rand
 DEPS_fourcc := syntax std
 DEPS_hexfloat := syntax std
-DEPS_num := std
+DEPS_num := std rand
 DEPS_test := std extra collections getopts serialize term
 DEPS_time := std serialize
+DEPS_rand := std
 
 TOOL_DEPS_compiletest := test green rustuv getopts
 TOOL_DEPS_rustdoc := rustdoc native

src/doc/guide-tasks.md

@@ -50,13 +50,13 @@ concurrency at this writing:
 * [`sync::DuplexStream`] - An extension of `pipes::stream` that allows both sending and receiving,
 * [`sync::SyncChan`] - An extension of `pipes::stream` that provides synchronous message sending,
 * [`sync::SyncPort`] - An extension of `pipes::stream` that acknowledges each message received,
-* [`sync::rendezvous`] - Creates a stream whose channel, upon sending a message, blocks until the 
+* [`sync::rendezvous`] - Creates a stream whose channel, upon sending a message, blocks until the
     message is received.
 * [`sync::Arc`] - The Arc (atomically reference counted) type, for safely sharing immutable data,
 * [`sync::RWArc`] - A dual-mode Arc protected by a reader-writer lock,
 * [`sync::MutexArc`] - An Arc with mutable data protected by a blocking mutex,
 * [`sync::Semaphore`] - A counting, blocking, bounded-waiting semaphore,
-* [`sync::Mutex`] - A blocking, bounded-waiting, mutual exclusion lock with an associated 
+* [`sync::Mutex`] - A blocking, bounded-waiting, mutual exclusion lock with an associated
     FIFO condition variable,
 * [`sync::RWLock`] - A blocking, no-starvation, reader-writer lock with an associated condvar,
 * [`sync::Barrier`] - A barrier enables multiple tasks to synchronize the beginning
@@ -343,8 +343,8 @@ a single large vector of floats. Each task needs the full vector to perform its
 
 ~~~
 # extern crate sync;
+ extern crate rand;
 # use std::vec;
-# use std::rand;
 use sync::Arc;
 
 fn pnorm(nums: &~[f64], p: uint) -> f64 {
@@ -376,9 +376,9 @@ created by the line
 
 ~~~
 # extern crate sync;
+# extern crate rand;
 # use sync::Arc;
 # use std::vec;
-# use std::rand;
 # fn main() {
 # let numbers = vec::from_fn(1000000, |_| rand::random::<f64>());
 let numbers_arc=Arc::new(numbers);
@@ -389,9 +389,9 @@ and a clone of it is sent to each task
 
 ~~~
 # extern crate sync;
+# extern crate rand;
 # use sync::Arc;
 # use std::vec;
-# use std::rand;
 # fn main() {
 # let numbers=vec::from_fn(1000000, |_| rand::random::<f64>());
 # let numbers_arc = Arc::new(numbers);
@@ -406,9 +406,9 @@ Each task recovers the underlying data by
 
 ~~~
 # extern crate sync;
+# extern crate rand;
 # use sync::Arc;
 # use std::vec;
-# use std::rand;
 # fn main() {
 # let numbers=vec::from_fn(1000000, |_| rand::random::<f64>());
 # let numbers_arc=Arc::new(numbers);

src/doc/tutorial.md

@@ -2529,7 +2529,7 @@ of type `ABC` can be randomly generated and converted to a string:
 #[deriving(Eq)]
 struct Circle { radius: f64 }
 
-#[deriving(Rand, Show)]
+#[deriving(Clone, Show)]
 enum ABC { A, B, C }
 ~~~
 

src/etc/generate-deriving-span-tests.py

@@ -39,6 +39,7 @@
 
 #[feature(struct_variant)];
 extern crate extra;
+extern crate rand;
 
 {error_deriving}
 struct Error;

src/etc/ziggurat_tables.py

@@ -11,7 +11,7 @@
 # except according to those terms.
 
 # This creates the tables used for distributions implemented using the
-# ziggurat algorithm in `std::rand::distributions;`. They are
+# ziggurat algorithm in `rand::distributions;`. They are
 # (basically) the tables as used in the ZIGNOR variant (Doornik 2005).
 # They are changed rarely, so the generated file should be checked in
 # to git.

src/libcollections/bitv.rs

@@ -947,8 +947,8 @@ mod tests {
 
     use std::uint;
     use std::vec;
-    use std::rand;
-    use std::rand::Rng;
+    use rand;
+    use rand::Rng;
 
     static BENCH_BITS : uint = 1 << 14;
 

src/libcollections/deque.rs

@@ -44,8 +44,9 @@ pub mod bench {
     extern crate test;
     use self::test::BenchHarness;
     use std::container::MutableMap;
-    use std::{vec, rand};
-    use std::rand::Rng;
+    use std::vec;
+    use rand;
+    use rand::Rng;
 
     pub fn insert_rand_n<M:MutableMap<uint,uint>>(n: uint,
                                                   map: &mut M,

src/libcollections/dlist.rs

@@ -633,7 +633,7 @@ mod tests {
     extern crate test;
     use self::test::BenchHarness;
     use deque::Deque;
-    use std::rand;
+    use rand;
     use super::{DList, Node, ListInsertion};
 
     pub fn check_links<T>(list: &DList<T>) {

src/libcollections/hashmap.rs

@@ -61,8 +61,8 @@ use std::iter::{FilterMap, Chain, Repeat, Zip};
 use std::iter;
 use std::mem::replace;
 use std::num;
-use std::rand::Rng;
-use std::rand;
+use rand::Rng;
+use rand;
 use std::vec::{Items, MutItems};
 use std::vec_ng::Vec;
 use std::vec_ng;

src/libcollections/lib.rs

@@ -23,6 +23,8 @@
 #[allow(unrecognized_lint)];
 #[allow(default_type_param_usage)];
 
+extern crate rand;
+
 #[cfg(test)] extern crate test;
 
 pub use bitv::Bitv;