Change vec slice to use uint, add push/pop/shift/unshift.

src/lib/_vec.rs

@@ -85,19 +85,42 @@ fn print_debug_info[T](vec[T] v) {
 }
 
 // Returns elements from [start..end) from v.
-fn slice[T](vec[T] v, int start, int end) -> vec[T] {
-    check (0 <= start);
+fn slice[T](vec[T] v, uint start, uint end) -> vec[T] {
     check (start <= end);
-    check (end <= (len[T](v) as int));
-    auto result = alloc[T]((end - start) as uint);
-    let int i = start;
+    check (end <= len[T](v));
+    auto result = alloc[T](end - start);
+    let uint i = start;
     while (i < end) {
         result += vec(v.(i));
-        i += 1;
+        i += 1u;
     }
     ret result;
 }
 
+fn shift[T](vec[T] v) -> vec[T] {
+    check(len[T](v) > 0u);
+    ret slice[T](v, 1u, len[T](v));
+}
+
+fn pop[T](vec[T] v) -> vec[T] {
+    check(len[T](v) > 0u);
+    ret slice[T](v, 0u, len[T](v) - 1u);
+}
+
+fn push[T](vec[T] v, &T t) -> vec[T] {
+    v += t;
+    ret v;
+}
+
+fn unshift[T](vec[T] v, &T t) -> vec[T] {
+    auto res = alloc[T](len[T](v) + 1u);
+    res += t;
+    for (T t_ in v) {
+        res += t_;
+    }
+    ret res;
+}
+
 fn grow[T](&mutable vec[T] v, int n, &T initval) {
     let int i = n;
     while (i > 0) {

src/test/run-pass/lib-vec.rs

 use std;
 
 fn test_init_elt() {
-  let vec[uint] v = std._vec.init_elt[uint](5 as uint, 3 as uint);
-  check (std._vec.len[uint](v) == (3 as uint));
-  check (v.(0) == (5 as uint));
-  check (v.(1) == (5 as uint));
-  check (v.(2) == (5 as uint));
+  let vec[uint] v = std._vec.init_elt[uint](5u, 3u);
+  check (std._vec.len[uint](v) == 3u);
+  check (v.(0) == 5u);
+  check (v.(1) == 5u);
+  check (v.(2) == 5u);
 }
 
 fn id(uint x) -> uint {
@@ -13,19 +13,19 @@ fn id(uint x) -> uint {
 }
 fn test_init_fn() {
   let fn(uint)->uint op = id;
-  let vec[uint] v = std._vec.init_fn[uint](op, (5 as uint));
-  check (std._vec.len[uint](v) == (5 as uint));
-  check (v.(0) == (0 as uint));
-  check (v.(1) == (1 as uint));
-  check (v.(2) == (2 as uint));
-  check (v.(3) == (3 as uint));
-  check (v.(4) == (4 as uint));
+  let vec[uint] v = std._vec.init_fn[uint](op, 5u);
+  check (std._vec.len[uint](v) == 5u);
+  check (v.(0) == 0u);
+  check (v.(1) == 1u);
+  check (v.(2) == 2u);
+  check (v.(3) == 3u);
+  check (v.(4) == 4u);
 }
 
 fn test_slice() {
   let vec[int] v = vec(1,2,3,4,5);
-  auto v2 = std._vec.slice[int](v, 2, 4);
-  check (std._vec.len[int](v2) == (2 as uint));
+  auto v2 = std._vec.slice[int](v, 2u, 4u);
+  check (std._vec.len[int](v2) == 2u);
   check (v2.(0) == 3);
   check (v2.(1) == 4);
 }