1 files changed, 36 insertions, 6 deletions

diff --git a/src/lib/_vec.rs b/src/lib/_vec.rs
index 86733fb5..3074df2c 100644
--- a/src/lib/_vec.rs
+++ b/src/lib/_vec.rs
@@ -1,21 +1,39 @@
 import vbuf = rustrt.vbuf;
+import op = util.operator;
 
 native "rust" mod rustrt {
   type vbuf;
   fn vec_buf[T](vec[T] v) -> vbuf;
   fn vec_len[T](vec[T] v) -> uint;
-  fn vec_alloc[T](int n_elts) -> vec[T];
+  fn vec_alloc[T](uint n_elts) -> vec[T];
 }
 
-fn alloc[T](int n_elts) -> vec[T] {
+fn alloc[T](uint n_elts) -> vec[T] {
   ret rustrt.vec_alloc[T](n_elts);
 }
 
-fn init[T](&T t, int n_elts) -> vec[T] {
+type init_op[T] = fn(uint i) -> T;
+
+fn init_fn[T](&init_op[T] op, uint n_elts) -> vec[T] {
   let vec[T] v = alloc[T](n_elts);
-  let int i = n_elts;
-  while (i > 0) {
-    i -= 1;
+  let uint i = n_elts;
+  while (i > uint(0)) {
+    i -= uint(1);
+    v += vec(op(i));
+  }
+  ret v;
+}
+
+fn init_elt[T](&T t, uint n_elts) -> vec[T] {
+  // FIXME: should be:
+  // fn elt_op[X](X x, uint i) -> X { ret x; }
+  // auto inner = bind elt_op[T](t, _);
+  // ret init_fn[T](inner, n_elts);
+  // but this does not work presently.
+  let vec[T] v = alloc[T](n_elts);
+  let uint i = n_elts;
+  while (i > uint(0)) {
+    i -= uint(1);
     v += vec(t);
   }
   ret v;
@@ -39,3 +57,15 @@ fn grow[T](mutable vec[T] v, int n, T initval) -> vec[T] {
   }
   ret v;
 }
+
+fn map[T,U](&op[T,U] f, &vec[T] v) -> vec[U] {
+  // FIXME: should be
+  // let vec[U] u = alloc[U](len[T](v));
+  // but this does not work presently.
+  let vec[U] u = vec();
+  for (T ve in v) {
+    u += vec(f[T,U](ve));
+  }
+  ret u;
+}
+