Add support for for-loop

The semantics is similar to the C++11 range-based for:

list = 1 2 3
for i: $list
  print $i

Note that there is no scoping of any kind for the loop variable ('i' in
the above example).

See tests/loop/for.test for some examples/ideas.

In the future the plan is to also support more general while-loop as well
as break and continue.

1 files changed, 5 insertions, 3 deletions

diff --git a/build2/types.hxx b/build2/types.hxx
index f65d054..cf95a9d 100644
--- a/build2/types.hxx
+++ b/build2/types.hxx
@@ -55,6 +55,8 @@ namespace build2
   using std::uint64_t;
   using std::uintptr_t;
 
+  using uint64s = std::vector<uint64_t>;
+
   using std::size_t;
   using std::nullptr_t;
 
@@ -64,6 +66,9 @@ namespace build2
   using std::function;
   using std::reference_wrapper;
 
+  using strings = std::vector<string>;
+  using cstrings = std::vector<const char*>;
+
   using std::hash;
 
   using std::initializer_list;
@@ -77,9 +82,6 @@ namespace build2
   using butl::vector_view;  // <libbutl/vector-view.mxx>
   using butl::small_vector; // <libbutl/small-vector.mxx>
 
-  using strings = vector<string>;
-  using cstrings = vector<const char*>;
-
   using std::istream;
   using std::ostream;