---

yaml
---
r: 38779
b: refs/heads/incoming
c: d4432a7
h: refs/heads/master
i:
  38777: 0304a54
  38775: 8758126
v: v3

Author: 14427

[refs]

@@ -6,7 +6,7 @@ refs/heads/try: 3d5418789064fdb463e872a4e651af1c628a3650
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/ndm: f3868061cd7988080c30d6d5bf352a5a5fe2460b
 refs/heads/try2: a810c03263670238bccd64cabb12a23a46e3a278
-refs/heads/incoming: b2d5acd6bcf34da3c7a16e554f9249c4cb1cc846
+refs/heads/incoming: d4432a797450594ff78457fe3e516bb0aeaedfe0
 refs/heads/dist-snap: 22efa39382d41b084fde1719df7ae8ce5697d8c9
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596
 refs/tags/release-0.3: b5f0d0f648d9a6153664837026ba1be43d3e2503

branches/incoming/.gitignore

@@ -80,4 +80,3 @@ tmp.*.rs
 config.stamp
 .DS_Store
 src/etc/dl
-.settings/

branches/incoming/AUTHORS.txt

@@ -108,7 +108,6 @@ Tim Chevalier <[email protected]>
 Tom Lee <[email protected]>
 Tomoki Aonuma <[email protected]>
 Tycho Sci <[email protected]>
-Viktor Dahl <[email protected]>
 Vincent Belliard <[email protected]>
 Wade Mealing <[email protected]>
 Yasuhiro Fujii <[email protected]>

branches/incoming/doc/rust.md

@@ -1388,7 +1388,7 @@ declaring a function-local item.
 
 ~~~~~~~~{.ebnf .gram}
 let_decl : "let" pat [':' type ] ? [ init ] ? ';' ;
-init : [ '=' ] expr ;
+init : [ '=' | '<-' ] expr ;
 ~~~~~~~~
 
 A _slot declaration_ introduces a new set of slots, given by a pattern.
@@ -1728,6 +1728,38 @@ fn avg(v: &[float]) -> float {
 }
 ~~~~
 
+
+#### Binary move expressions
+
+A _binary move expression_ consists of an [lvalue](#lvalues-rvalues-and-temporaries) followed by a left-pointing
+arrow (`<-`) and an [rvalue](#lvalues-rvalues-and-temporaries) expression.
+
+Evaluating a move expression causes, as a side effect,
+the rvalue to be *moved* into the lvalue.
+If the rvalue was itself an lvalue, it must be a local variable,
+as it will be de-initialized in the process.
+
+Evaluating a move expression does not change reference counts,
+nor does it cause a deep copy of any owned structure pointed to by the moved rvalue.
+Instead, the move expression represents an indivisible *transfer of ownership*
+from the right-hand-side to the left-hand-side of the expression.
+No allocation or destruction is entailed.
+
+An example of three different move expressions:
+
+~~~~~~~~
+# let mut x = &[mut 0];
+# let a = &[mut 0];
+# let b = 0;
+# let y = {mut z: 0};
+# let c = 0;
+# let i = 0;
+
+x <- a;
+x[i] <- b;
+y.z <- c;
+~~~~~~~~
+
 #### Swap expressions
 
 A _swap expression_ consists of an [lvalue](#lvalues-rvalues-and-temporaries) followed by a bi-directional arrow (`<->`) and another [lvalue](#lvalues-rvalues-and-temporaries).
@@ -1760,15 +1792,21 @@ y.z <-> b.c;
 An _assignment expression_ consists of an [lvalue](#lvalues-rvalues-and-temporaries) expression followed by an
 equals sign (`=`) and an [rvalue](#lvalues-rvalues-and-temporaries) expression.
 
-Evaluating an assignment expression copies the expression on the right-hand side and stores it in the location on the left-hand side.
+Evaluating an assignment expression is equivalent to evaluating a [binary move
+expression](#binary-move-expressions) applied to a [unary copy
+expression](#unary-copy-expressions). For example, the following two
+expressions have the same effect:
 
 ~~~~
 # let mut x = 0;
 # let y = 0;
 
 x = y;
+x <- copy y;
 ~~~~
 
+The former is just more terse and familiar.
+
 #### Compound assignment expressions
 
 The `+`, `-`, `*`, `/`, `%`, `&`, `|`, `^`, `<<`, and `>>`
@@ -1795,7 +1833,7 @@ as
 == !=
 &&
 ||
-= <->
+= <- <->
 ~~~~
 
 Operators at the same precedence level are evaluated left-to-right.
@@ -2507,7 +2545,7 @@ let a: List<int> = Cons(7, @Cons(13, @Nil));
 
 > **Note:** Records are not nominal types, thus do not directly support recursion, visibility control,
 > out-of-order field initialization, or coherent trait implementation.
-> Records are therefore deprecated and will be removed in future versions of Rust.
+> Records are therefore deprecared and will be removed in future versions of Rust.
 > [Structure types](#structure-types) should be used instead.
 
 The record type-constructor forms a new heterogeneous product of values.

branches/incoming/doc/tutorial-borrowed-ptr.md

@@ -429,7 +429,7 @@ fn example5c(x: @S) -> int {
         let y = &v.g;
         ...
     }
-    x.f = move v;          // Replace x.f
+    x.f <- v;          // Replace x.f
     ...
 # return 0;
 }

branches/incoming/doc/tutorial.md

@@ -1205,6 +1205,11 @@ to other tasks. The sending task will give up ownership of the box,
 and won't be able to access it afterwards. The receiving task will
 become the sole owner of the box.
 
+> ***Note:*** This discussion of copying vs. moving does not account
+> for the "last use" rules that automatically promote copy operations
+> to moves. We plan to remove last use from the language in
+> favor of explicit moves.
+
 ## Borrowed pointers
 
 Rust borrowed pointers are a general purpose reference/pointer type,

branches/incoming/mk/rt.mk

@@ -72,6 +72,7 @@ RUNTIME_CS_$(1) := \
               rt/rust_shape.cpp \
               rt/rust_abi.cpp \
               rt/rust_debug.cpp \
+              rt/rust_box_annihilator.cpp \
               rt/memory_region.cpp \
               rt/boxed_region.cpp \
               rt/arch/$$(HOST_$(1))/context.cpp \

branches/incoming/src/cargo/cargo.rs

@@ -1491,7 +1491,7 @@ fn print_pkg(s: @Source, p: &Package) {
 fn print_source(s: @Source) {
     info(s.name + ~" (" + s.url + ~")");
 
-    let pks = sort::merge_sort(sys::shape_lt, s.packages.get());
+    let pks = sort::merge_sort(s.packages.get(), sys::shape_lt);
     let l = vec::len(pks);
 
     print(io::with_str_writer(|writer| {

branches/incoming/src/fuzzer/ivec_fuzz.rs

@@ -2,7 +2,7 @@
 
 Idea: provide functions for 'exhaustive' and 'random' modification of vecs.
 
-  two functions, "return all edits" and "return a random edit" = move-
+  two functions, "return all edits" and "return a random edit" <--
     leaning toward this model or two functions, "return the number of
     possible edits" and "return edit #n"
 

branches/incoming/src/libcore/at_vec.rs

@@ -136,23 +136,12 @@ pub pure fn from_elem<T: Copy>(n_elts: uint, t: T) -> @[T] {
 #[cfg(notest)]
 pub mod traits {
     #[legacy_exports];
-
-    #[cfg(stage0)]
     pub impl<T: Copy> @[T] : Add<&[const T],@[T]> {
         #[inline(always)]
         pure fn add(rhs: & &[const T]) -> @[T] {
             append(self, (*rhs))
         }
     }
-
-    #[cfg(stage1)]
-    #[cfg(stage2)]
-    pub impl<T: Copy> @[T] : Add<&[const T],@[T]> {
-        #[inline(always)]
-        pure fn add(rhs: & &self/[const T]) -> @[T] {
-            append(self, (*rhs))
-        }
-    }
 }
 
 #[cfg(test)]