Move std::{trie, hashmap} to libcollections

These two containers are indeed collections, so their place is in
libcollections, not in libstd. There will always be a hash map as part of the
standard distribution of Rust, but by moving it out of the standard library it
makes libstd that much more portable to more platforms and environments.

This conveniently also removes the stuttering of 'std::hashmap::HashMap',
although 'collections::HashMap' is only one character shorter.

Author: alexcrichton

mk/crates.mk

@@ -69,7 +69,7 @@ DEPS_flate := std native:miniz
 DEPS_arena := std collections
 DEPS_glob := std
 DEPS_serialize := std
-DEPS_term := std
+DEPS_term := std collections
 DEPS_semver := std
 DEPS_uuid := std serialize
 DEPS_sync := std

src/doc/rust.md

@@ -467,7 +467,7 @@ expression context, the final namespace qualifier is omitted.
 Two examples of paths with type arguments:
 
 ~~~~
-# use std::hashmap::HashMap;
+# struct HashMap<K, V>;
 # fn f() {
 # fn id<T>(t: T) -> T { t }
 type T = HashMap<int,~str>;  // Type arguments used in a type expression

src/doc/tutorial.md

@@ -1977,8 +1977,8 @@ illegal to copy and pass by value.
 Generic `type`, `struct`, and `enum` declarations follow the same pattern:
 
 ~~~~
-use std::hashmap::HashMap;
-type Set<T> = HashMap<T, ()>;
+extern crate collections;
+type Set<T> = collections::HashMap<T, ()>;
 
 struct Stack<T> {
     elements: ~[T]
@@ -1988,6 +1988,7 @@ enum Option<T> {
     Some(T),
     None
 }
+# fn main() {}
 ~~~~
 
 These declarations can be instantiated to valid types like `Set<int>`,

src/etc/combine-tests.py

@@ -55,6 +55,8 @@ def scrub(b):
 #[crate_id=\"run_pass_stage2#0.1\"];
 #[feature(globs, macro_rules, struct_variant, managed_boxes)];
 #[allow(warnings)];
+extern crate collections;
+extern crate extra;
 """
 )
 for t in stage2_tests:

src/libstd/hashmap.rs src/libcollections/hashmap.rs

@@ -16,7 +16,7 @@
 //! # Example
 //!
 //! ```rust
-//! use std::hashmap::HashMap;
+//! use collections::HashMap;
 //!
 //! // type inference lets us omit an explicit type signature (which
 //! // would be `HashMap<&str, &str>` in this example).
@@ -52,24 +52,20 @@
 //! }
 //! ```
 
-use container::{Container, Mutable, Map, MutableMap, Set, MutableSet};
-use clone::Clone;
-use cmp::{Eq, Equiv, max};
-use default::Default;
-use fmt;
-use hash_old::Hash;
-use iter;
-use iter::{Iterator, FromIterator, Extendable};
-use iter::{FilterMap, Chain, Repeat, Zip};
-use mem::replace;
-use num;
-use option::{None, Option, Some};
-use rand::Rng;
-use rand;
-use result::{Ok, Err};
-use vec::{ImmutableVector, MutableVector, OwnedVector, Items, MutItems};
-use vec_ng;
-use vec_ng::Vec;
+use std::cmp::max;
+use std::fmt;
+use std::hash_old::Hash;
+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 std::vec::{Items, MutItems};
+use std::vec_ng::Vec;
+use std::vec_ng;
+
+use serialize::{Encodable, Decodable, Encoder, Decoder};
 
 static INITIAL_CAPACITY: uint = 32u; // 2^5
 
@@ -404,7 +400,7 @@ impl<K: Hash + Eq, V> HashMap<K, V> {
     /// # Example
     ///
     /// ```rust
-    /// use std::hashmap::HashMap;
+    /// use collections::HashMap;
     ///
     /// // map some strings to vectors of strings
     /// let mut map = HashMap::<~str, ~[~str]>::new();
@@ -613,6 +609,10 @@ impl<A: fmt::Show + Hash + Eq, B: fmt::Show> fmt::Show for HashMap<A, B> {
     }
 }
 
+impl<K: fmt::Show + Hash + Eq, V: fmt::Show> ToStr for HashMap<K, V> {
+    fn to_str(&self) -> ~str { format!("{}", *self) }
+}
+
 /// HashMap iterator
 #[deriving(Clone)]
 pub struct Entries<'a, K, V> {
@@ -891,6 +891,10 @@ impl<A: fmt::Show + Hash + Eq> fmt::Show for HashSet<A> {
     }
 }
 
+impl<A: fmt::Show + Hash + Eq> ToStr for HashSet<A> {
+    fn to_str(&self) -> ~str { format!("{}", *self) }
+}
+
 impl<K: Eq + Hash> FromIterator<K> for HashSet<K> {
     fn from_iterator<T: Iterator<K>>(iter: &mut T) -> HashSet<K> {
         let (lower, _) = iter.size_hint();
@@ -919,12 +923,75 @@ pub type SetAlgebraItems<'a, T> =
     FilterMap<'static,(&'a HashSet<T>, &'a T), &'a T,
               Zip<Repeat<&'a HashSet<T>>,SetItems<'a,T>>>;
 
+impl<
+    E: Encoder,
+    K: Encodable<E> + Hash + IterBytes + Eq,
+    V: Encodable<E>
+> Encodable<E> for HashMap<K, V> {
+    fn encode(&self, e: &mut E) {
+        e.emit_map(self.len(), |e| {
+            let mut i = 0;
+            for (key, val) in self.iter() {
+                e.emit_map_elt_key(i, |e| key.encode(e));
+                e.emit_map_elt_val(i, |e| val.encode(e));
+                i += 1;
+            }
+        })
+    }
+}
+
+impl<
+    D: Decoder,
+    K: Decodable<D> + Hash + IterBytes + Eq,
+    V: Decodable<D>
+> Decodable<D> for HashMap<K, V> {
+    fn decode(d: &mut D) -> HashMap<K, V> {
+        d.read_map(|d, len| {
+            let mut map = HashMap::with_capacity(len);
+            for i in range(0u, len) {
+                let key = d.read_map_elt_key(i, |d| Decodable::decode(d));
+                let val = d.read_map_elt_val(i, |d| Decodable::decode(d));
+                map.insert(key, val);
+            }
+            map
+        })
+    }
+}
+
+impl<
+    S: Encoder,
+    T: Encodable<S> + Hash + IterBytes + Eq
+> Encodable<S> for HashSet<T> {
+    fn encode(&self, s: &mut S) {
+        s.emit_seq(self.len(), |s| {
+            let mut i = 0;
+            for e in self.iter() {
+                s.emit_seq_elt(i, |s| e.encode(s));
+                i += 1;
+            }
+        })
+    }
+}
+
+impl<
+    D: Decoder,
+    T: Decodable<D> + Hash + IterBytes + Eq
+> Decodable<D> for HashSet<T> {
+    fn decode(d: &mut D) -> HashSet<T> {
+        d.read_seq(|d, len| {
+            let mut set = HashSet::with_capacity(len);
+            for i in range(0u, len) {
+                set.insert(d.read_seq_elt(i, |d| Decodable::decode(d)));
+            }
+            set
+        })
+    }
+}
 
 #[cfg(test)]
 mod test_map {
-    use prelude::*;
-    use super::*;
-    use fmt;
+    use super::{HashMap, HashSet};
+    use std::fmt;
 
     #[test]
     fn test_create_capacity_zero() {
@@ -1180,14 +1247,49 @@ mod test_map {
         assert!(table_str == ~"{1: s2, 3: s4}" || table_str == ~"{3: s4, 1: s2}");
         assert_eq!(format!("{}", empty), ~"{}");
     }
+
+    struct StructWithToStrWithoutEqOrHash {
+        value: int
+    }
+
+    impl fmt::Show for StructWithToStrWithoutEqOrHash {
+        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+            write!(f.buf, "s{}", self.value)
+        }
+    }
+
+    #[test]
+    fn test_hashset() {
+        let mut set: HashSet<int> = HashSet::new();
+        let empty_set: HashSet<int> = HashSet::new();
+
+        set.insert(1);
+        set.insert(2);
+
+        let set_str = set.to_str();
+
+        assert!(set_str == ~"{1, 2}" || set_str == ~"{2, 1}");
+        assert_eq!(empty_set.to_str(), ~"{}");
+    }
+
+    #[test]
+    fn test_hashmap() {
+        let mut table: HashMap<int, StructWithToStrWithoutEqOrHash> = HashMap::new();
+        let empty: HashMap<int, StructWithToStrWithoutEqOrHash> = HashMap::new();
+
+        table.insert(3, StructWithToStrWithoutEqOrHash { value: 4 });
+        table.insert(1, StructWithToStrWithoutEqOrHash { value: 2 });
+
+        let table_str = table.to_str();
+
+        assert!(table_str == ~"{1: s2, 3: s4}" || table_str == ~"{3: s4, 1: s2}");
+        assert_eq!(empty.to_str(), ~"{}");
+    }
 }
 
 #[cfg(test)]
 mod test_set {
-    use super::*;
-    use prelude::*;
-    use container::Container;
-    use vec::ImmutableEqVector;
+    use super::HashSet;
 
     #[test]
     fn test_disjoint() {

src/libcollections/lib.rs

@@ -27,21 +27,25 @@ pub use btree::BTree;
 pub use deque::Deque;
 pub use dlist::DList;
 pub use enum_set::EnumSet;
+pub use hashmap::{HashMap, HashSet};
 pub use list::List;
 pub use lru_cache::LruCache;
 pub use priority_queue::PriorityQueue;
 pub use ringbuf::RingBuf;
 pub use smallintmap::SmallIntMap;
 pub use treemap::{TreeMap, TreeSet};
+pub use trie::{TrieMap, TrieSet};
 
 pub mod bitv;
 pub mod btree;
 pub mod deque;
 pub mod dlist;
 pub mod enum_set;
+pub mod hashmap;
 pub mod list;
 pub mod lru_cache;
 pub mod priority_queue;
 pub mod ringbuf;
 pub mod smallintmap;
 pub mod treemap;
+pub mod trie;

src/libcollections/lru_cache.rs

@@ -38,11 +38,12 @@
 //! ```
 
 use std::container::Container;
-use std::hashmap::HashMap;
 use std::to_bytes::Cb;
 use std::ptr;
 use std::cast;
 
+use HashMap;
+
 struct KeyRef<K> { k: *K }
 
 struct LruEntry<K, V> {