rustc: Add a stub crate reader module for "use" directives

2 files changed, 32 insertions, 0 deletions

diff --git a/src/comp/front/ast.rs b/src/comp/front/ast.rs
index a7ff64fa..3de72406 100644
--- a/src/comp/front/ast.rs
+++ b/src/comp/front/ast.rs
@@ -21,6 +21,7 @@ type ty_param = rec(ident ident, def_id id);
 // Annotations added during successive passes.
 tag ann {
     ann_none;
+    ann_crate(@external_crate_info);
     ann_type(@middle.ty.t, option.t[vec[@middle.ty.t]] /* ty param substs */);
 }
 
@@ -370,6 +371,9 @@ tag native_item_ {
     native_item_fn(ident, fn_decl, vec[ty_param], def_id, ann);
 }
 
+// TODO: Actually store something here.
+type external_crate_info = ();
+
 fn index_view_item(mod_index index, @view_item it) {
     alt (it.node) {
         case(ast.view_item_use(?id, _, _)) {
diff --git a/src/comp/front/creader.rs b/src/comp/front/creader.rs
new file mode 100644
index 00000000..4564ae2b
--- /dev/null
+++ b/src/comp/front/creader.rs
@@ -0,0 +1,28 @@
+// -*- rust -*-
+
+import driver.session;
+import front.ast;
+import middle.fold;
+import util.common;
+import util.common.span;
+import std.map.hashmap;
+
+// TODO: map to a real type here.
+type env = @hashmap[str, @ast.external_crate_info];
+
+fn fold_view_item_use(&env e, &span sp, ast.ident ident,
+        vec[@ast.meta_item] meta_items, ast.def_id id) -> @ast.view_item {
+    // TODO: find the crate
+
+    auto viu = ast.view_item_use(ident, meta_items, id);
+    ret @fold.respan[ast.view_item_](sp, viu);
+}
+
+// Reads external crates referenced by "use" directives.
+fn read_crates(session.session sess, @ast.crate crate) -> @ast.crate {
+    auto external_crates = @common.new_str_hash[@ast.external_crate_info]();
+    auto f = fold_view_item_use;
+    auto fld = @rec(fold_view_item_use=f with *fold.new_identity_fold[env]());
+    ret fold.fold_crate[env](external_crates, fld, crate);
+}
+