auto merge of #7373 : thestinger/rust/iterator, r=huonw

doc/tutorial.md

@@ -1552,13 +1552,6 @@ fn each(v: &[int], op: &fn(v: &int)) {
 }
 ~~~~
 
-As an aside, the reason we pass in a *pointer* to an integer rather
-than the integer itself is that this is how the actual `each()`
-function for vectors works. `vec::each` though is a
-[generic](#generics) function, so must be efficient to use for all
-types. Passing the elements by pointer avoids copying potentially
-large objects.
-
 As a caller, if we use a closure to provide the final operator
 argument, we can write it in a way that has a pleasant, block-like
 structure.
@@ -1616,6 +1609,9 @@ To enable `debug!` logging, set the RUST_LOG environment variable to the name of
 
 ## For loops
 
+> ***Note:*** The closure-based protocol used `for` loop is on the way out. The `for` loop will
+> use iterator objects in the future instead.
+
 The most common way to express iteration in Rust is with a `for`
 loop. Like `do`, `for` is a nice syntax for describing control flow
 with closures.  Additionally, within a `for` loop, `break`, `loop`,
@@ -1640,7 +1636,16 @@ fn each(v: &[int], op: &fn(v: &int) -> bool) -> bool {
 And using this function to iterate over a vector:
 
 ~~~~
-# use each = std::vec::each;
+# fn each(v: &[int], op: &fn(v: &int) -> bool) -> bool {
+#    let mut n = 0;
+#    while n < v.len() {
+#        if !op(&v[n]) {
+#            return false;
+#        }
+#        n += 1;
+#    }
+#    return true;
+# }
 each([2, 4, 8, 5, 16], |n| {
     if *n % 2 != 0 {
         println("found odd number!");
@@ -1656,7 +1661,16 @@ out of the loop, you just write `break`. To skip ahead
 to the next iteration, write `loop`.
 
 ~~~~
-# use each = std::vec::each;
+# fn each(v: &[int], op: &fn(v: &int) -> bool) -> bool {
+#    let mut n = 0;
+#    while n < v.len() {
+#        if !op(&v[n]) {
+#            return false;
+#        }
+#        n += 1;
+#    }
+#    return true;
+# }
 for each([2, 4, 8, 5, 16]) |n| {
     if *n % 2 != 0 {
         println("found odd number!");
@@ -1671,7 +1685,16 @@ normally allowed in closures, in a block that appears as the body of a
 the enclosing function, not just the loop body.
 
 ~~~~
-# use each = std::vec::each;
+# fn each(v: &[int], op: &fn(v: &int) -> bool) -> bool {
+#    let mut n = 0;
+#    while n < v.len() {
+#        if !op(&v[n]) {
+#            return false;
+#        }
+#        n += 1;
+#    }
+#    return true;
+# }
 fn contains(v: &[int], elt: int) -> bool {
     for each(v) |x| {
         if (*x == elt) { return true; }
@@ -1686,7 +1709,16 @@ In these situations it can be convenient to lean on Rust's
 argument patterns to bind `x` to the actual value, not the pointer.
 
 ~~~~
-# use each = std::vec::each;
+# fn each(v: &[int], op: &fn(v: &int) -> bool) -> bool {
+#    let mut n = 0;
+#    while n < v.len() {
+#        if !op(&v[n]) {
+#            return false;
+#        }
+#        n += 1;
+#    }
+#    return true;
+# }
 # fn contains(v: &[int], elt: int) -> bool {
     for each(v) |&x| {
         if (x == elt) { return true; }
@@ -1841,10 +1873,9 @@ vector consisting of the result of applying `function` to each element
 of `vector`:
 
 ~~~~
-# use std::vec;
 fn map<T, U>(vector: &[T], function: &fn(v: &T) -> U) -> ~[U] {
     let mut accumulator = ~[];
-    for vec::each(vector) |element| {
+    for vector.iter().advance |element| {
         accumulator.push(function(element));
     }
     return accumulator;

src/compiletest/runtest.rs

@@ -529,7 +529,7 @@ fn compose_and_run_compiler(
     let extra_link_args = ~[~"-L",
                             aux_output_dir_name(config, testfile).to_str()];
 
-    for vec::each(props.aux_builds) |rel_ab| {
+    for props.aux_builds.iter().advance |rel_ab| {
         let abs_ab = config.aux_base.push_rel(&Path(*rel_ab));
         let aux_args =
             make_compile_args(config, props, ~[~"--lib"] + extra_link_args,

src/libextra/arc.rs

@@ -521,6 +521,7 @@ mod tests {
     use core::cell::Cell;
     use core::comm;
     use core::task;
+    use core::uint;
 
     #[test]
     fn manually_share_arc() {
@@ -790,18 +791,20 @@ mod tests {
                 }
                 assert_eq!(*state, 42);
                 *state = 31337;
+                // FIXME: #7372: hits type inference bug with iterators
                 // send to other readers
-                for vec::each(reader_convos) |x| {
-                    match *x {
+                for uint::range(0, reader_convos.len()) |i| {
+                    match reader_convos[i] {
                         (ref rc, _) => rc.send(()),
                     }
                 }
             }
             let read_mode = arc.downgrade(write_mode);
             do (&read_mode).read |state| {
+                // FIXME: #7372: hits type inference bug with iterators
                 // complete handshake with other readers
-                for vec::each(reader_convos) |x| {
-                    match *x {
+                for uint::range(0, reader_convos.len()) |i| {
+                    match reader_convos[i] {
                         (_, ref rp) => rp.recv(),
                     }
                 }

src/libextra/getopts.rs

@@ -418,10 +418,11 @@ pub fn opts_str(mm: &Matches, names: &[~str]) -> ~str {
  */
 pub fn opt_strs(mm: &Matches, nm: &str) -> ~[~str] {
     let mut acc: ~[~str] = ~[];
-    for vec::each(opt_vals(mm, nm)) |v| {
+    let r = opt_vals(mm, nm);
+    for r.iter().advance |v| {
         match *v { Val(ref s) => acc.push(copy *s), _ => () }
     }
-    return acc;
+    acc
 }
 
 /// Returns the string argument supplied to a matching option or none

src/libextra/json.rs

@@ -1123,7 +1123,7 @@ impl Eq for Json {
                     &Object(ref d1) => {
                         if d0.len() == d1.len() {
                             let mut equal = true;
-                            for d0.each |k, v0| {
+                            for d0.iter().advance |(k, v0)| {
                                 match d1.find(k) {
                                     Some(v1) if v0 == v1 => { },
                                     _ => { equal = false; break }
@@ -1186,12 +1186,12 @@ impl Ord for Json {
                         let mut d1_flat = ~[];
 
                         // FIXME #4430: this is horribly inefficient...
-                        for d0.each |k, v| {
+                        for d0.iter().advance |(k, v)| {
                              d0_flat.push((@copy *k, @copy *v));
                         }
                         d0_flat.qsort();
 
-                        for d1.each |k, v| {
+                        for d1.iter().advance |(k, v)| {
                             d1_flat.push((@copy *k, @copy *v));
                         }
                         d1_flat.qsort();
@@ -1326,7 +1326,7 @@ impl<A:ToJson> ToJson for ~[A] {
 impl<A:ToJson + Copy> ToJson for HashMap<~str, A> {
     fn to_json(&self) -> Json {
         let mut d = HashMap::new();
-        for self.each |key, value| {
+        for self.iter().advance |(key, value)| {
             d.insert(copy *key, value.to_json());
         }
         Object(~d)

src/libextra/net_url.rs

@@ -207,7 +207,7 @@ pub fn encode_form_urlencoded(m: &HashMap<~str, ~[~str]>) -> ~str {
     let mut out = ~"";
     let mut first = true;
 
-    for m.each |key, values| {
+    for m.iter().advance |(key, values)| {
         let key = encode_plus(*key);
 
         for values.iter().advance |value| {

src/libextra/serialize.rs

@@ -710,7 +710,7 @@ impl<
     fn encode(&self, e: &mut E) {
         do e.emit_map(self.len()) |e| {
             let mut i = 0;
-            for self.each |key, val| {
+            for self.iter().advance |(key, val)| {
                 e.emit_map_elt_key(i, |e| key.encode(e));
                 e.emit_map_elt_val(i, |e| val.encode(e));
                 i += 1;
@@ -744,7 +744,7 @@ impl<
     fn encode(&self, s: &mut S) {
         do s.emit_seq(self.len()) |s| {
             let mut i = 0;
-            for self.each |e| {
+            for self.iter().advance |e| {
                 s.emit_seq_elt(i, |s| e.encode(s));
                 i += 1;
             }

src/libextra/smallintmap.rs

@@ -56,38 +56,6 @@ impl<V> Map<uint, V> for SmallIntMap<V> {
         self.find(key).is_some()
     }
 
-    /// Visit all key-value pairs in order
-    fn each<'a>(&'a self, it: &fn(&uint, &'a V) -> bool) -> bool {
-        for uint::range(0, self.v.len()) |i| {
-            match self.v[i] {
-              Some(ref elt) => if !it(&i, elt) { return false; },
-              None => ()
-            }
-        }
-        return true;
-    }
-
-    /// Visit all keys in order
-    fn each_key(&self, blk: &fn(key: &uint) -> bool) -> bool {
-        self.each(|k, _| blk(k))
-    }
-
-    /// Visit all values in order
-    fn each_value<'a>(&'a self, blk: &fn(value: &'a V) -> bool) -> bool {
-        self.each(|_, v| blk(v))
-    }
-
-    /// Iterate over the map and mutate the contained values
-    fn mutate_values(&mut self, it: &fn(&uint, &mut V) -> bool) -> bool {
-        for uint::range(0, self.v.len()) |i| {
-            match self.v[i] {
-              Some(ref mut elt) => if !it(&i, elt) { return false; },
-              None => ()
-            }
-        }
-        return true;
-    }
-
     /// Return a reference to the value corresponding to the key
     fn find<'a>(&'a self, key: &uint) -> Option<&'a V> {
         if *key < self.v.len() {
@@ -156,6 +124,38 @@ impl<V> SmallIntMap<V> {
     /// Create an empty SmallIntMap
     pub fn new() -> SmallIntMap<V> { SmallIntMap{v: ~[]} }
 
+    /// Visit all key-value pairs in order
+    pub fn each<'a>(&'a self, it: &fn(&uint, &'a V) -> bool) -> bool {
+        for uint::range(0, self.v.len()) |i| {
+            match self.v[i] {
+              Some(ref elt) => if !it(&i, elt) { return false; },
+              None => ()
+            }
+        }
+        return true;
+    }
+
+    /// Visit all keys in order
+    pub fn each_key(&self, blk: &fn(key: &uint) -> bool) -> bool {
+        self.each(|k, _| blk(k))
+    }
+
+    /// Visit all values in order
+    pub fn each_value<'a>(&'a self, blk: &fn(value: &'a V) -> bool) -> bool {
+        self.each(|_, v| blk(v))
+    }
+
+    /// Iterate over the map and mutate the contained values
+    pub fn mutate_values(&mut self, it: &fn(&uint, &mut V) -> bool) -> bool {
+        for uint::range(0, self.v.len()) |i| {
+            match self.v[i] {
+              Some(ref mut elt) => if !it(&i, elt) { return false; },
+              None => ()
+            }
+        }
+        return true;
+    }
+
     /// Visit all key-value pairs in reverse order
     pub fn each_reverse<'a>(&'a self, it: &fn(uint, &'a V) -> bool) -> bool {
         for uint::range_rev(self.v.len(), 0) |i| {

src/libextra/sync.rs

@@ -1094,7 +1094,8 @@ mod tests {
         };
         assert!(result.is_err());
         // child task must have finished by the time try returns
-        for vec::each(p.recv()) |p| { p.recv(); } // wait on all its siblings
+        let r = p.recv();
+        for r.iter().advance |p| { p.recv(); } // wait on all its siblings
         do m.lock_cond |cond| {
             let woken = cond.broadcast();
             assert_eq!(woken, 0);

src/libextra/treemap.rs

@@ -107,26 +107,6 @@ impl<K: TotalOrd, V> Map<K, V> for TreeMap<K, V> {
         self.find(key).is_some()
     }
 
-    /// Visit all key-value pairs in order
-    fn each<'a>(&'a self, f: &fn(&'a K, &'a V) -> bool) -> bool {
-        each(&self.root, f)
-    }
-
-    /// Visit all keys in order
-    fn each_key(&self, f: &fn(&K) -> bool) -> bool {
-        self.each(|k, _| f(k))
-    }
-
-    /// Visit all values in order
-    fn each_value<'a>(&'a self, f: &fn(&'a V) -> bool) -> bool {
-        self.each(|_, v| f(v))
-    }
-
-    /// Iterate over the map and mutate the contained values
-    fn mutate_values(&mut self, f: &fn(&K, &mut V) -> bool) -> bool {
-        mutate_values(&mut self.root, f)
-    }
-
     /// Return a reference to the value corresponding to the key
     fn find<'a>(&'a self, key: &K) -> Option<&'a V> {
         let mut current: &'a Option<~TreeNode<K, V>> = &self.root;
@@ -184,6 +164,26 @@ impl<K: TotalOrd, V> TreeMap<K, V> {
     /// Create an empty TreeMap
     pub fn new() -> TreeMap<K, V> { TreeMap{root: None, length: 0} }
 
+    /// Visit all key-value pairs in order
+    pub fn each<'a>(&'a self, f: &fn(&'a K, &'a V) -> bool) -> bool {
+        each(&self.root, f)
+    }
+
+    /// Visit all keys in order
+    pub fn each_key(&self, f: &fn(&K) -> bool) -> bool {
+        self.each(|k, _| f(k))
+    }
+
+    /// Visit all values in order
+    pub fn each_value<'a>(&'a self, f: &fn(&'a V) -> bool) -> bool {
+        self.each(|_, v| f(v))
+    }
+
+    /// Iterate over the map and mutate the contained values
+    pub fn mutate_values(&mut self, f: &fn(&K, &mut V) -> bool) -> bool {
+        mutate_values(&mut self.root, f)
+    }
+
     /// Visit all key-value pairs in reverse order
     pub fn each_reverse<'a>(&'a self, f: &fn(&'a K, &'a V) -> bool) -> bool {
         each_reverse(&self.root, f)

src/libextra/workcache.rs

@@ -146,7 +146,7 @@ impl WorkMap {
 impl<S:Encoder> Encodable<S> for WorkMap {
     fn encode(&self, s: &mut S) {
         let mut d = ~[];
-        for self.each |k, v| {
+        for self.iter().advance |(k, v)| {
             d.push((copy *k, copy *v))
         }
         sort::tim_sort(d);
@@ -320,7 +320,7 @@ impl TPrep for Prep {
     }
 
     fn all_fresh(&self, cat: &str, map: &WorkMap) -> bool {
-        for map.each |k, v| {
+        for map.iter().advance |(k, v)| {
             if ! self.is_fresh(cat, k.kind, k.name, *v) {
                 return false;
             }

src/librustc/metadata/cstore.rs

@@ -86,7 +86,7 @@ pub fn have_crate_data(cstore: &CStore, cnum: ast::crate_num) -> bool {
 
 pub fn iter_crate_data(cstore: &CStore,
                        i: &fn(ast::crate_num, @crate_metadata)) {
-    for cstore.metas.each |&k, &v| {
+    for cstore.metas.iter().advance |(&k, &v)| {
         i(k, v);
     }
 }