Implement tuple and tuple struct indexing

This allows code to access the fields of tuples and tuple structs:

    let x = (1i, 2i);
    assert_eq!(x.1, 2);

    struct Point(int, int);
    let origin = Point(0, 0);
    assert_eq!(origin.0, 0);
    assert_eq!(origin.1, 0);

1 files changed, 42 insertions, 0 deletions

diff --git a/src/test/compile-fail/borrow-tuple-fields.rs b/src/test/compile-fail/borrow-tuple-fields.rs
new file mode 100644
index 00000000000..519bad4e627
--- /dev/null
+++ b/src/test/compile-fail/borrow-tuple-fields.rs
@@ -0,0 +1,42 @@
+// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![feature(tuple_indexing)]
+
+struct Foo(Box<int>, int);
+
+struct Bar(int, int);
+
+fn main() {
+    let x = (box 1i, 2i);
+    let r = &x.0;
+    let y = x; //~ ERROR cannot move out of `x` because it is borrowed
+
+    let mut x = (1i, 2i);
+    let a = &x.0;
+    let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable because it is also borrowed as
+
+    let mut x = (1i, 2i);
+    let a = &mut x.0;
+    let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable more than once at a time
+
+
+    let x = Foo(box 1i, 2i);
+    let r = &x.0;
+    let y = x; //~ ERROR cannot move out of `x` because it is borrowed
+
+    let mut x = Bar(1i, 2i);
+    let a = &x.0;
+    let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable because it is also borrowed as
+
+    let mut x = Bar(1i, 2i);
+    let a = &mut x.0;
+    let b = &mut x.0; //~ ERROR cannot borrow `x.0` as mutable more than once at a time
+}