Add initial import support

1 files changed, 16 insertions, 0 deletions

diff --git a/build/scope b/build/scope
index 2b621e7..2eb8ac7 100644
--- a/build/scope
+++ b/build/scope
@@ -88,6 +88,8 @@ namespace build
 
   private:
     friend class scope_map;
+    friend class temp_scope;
+
     typedef path_map<scope>::const_iterator iterator;
 
     scope (): variables (*this) {}
@@ -97,6 +99,20 @@ namespace build
     scope* root_;
   };
 
+  // Temporary scope. The idea is to be able to create a temporary
+  // scope in order not to change the variables in the current scope.
+  // Such a scope is not entered in to the scope map. As a result it
+  // can only be used as a temporary set of variables. In particular,
+  // defining targets/prerequsites directly in such a scope will surely
+  // end up badly. Defining any nested scopes will be as if defining
+  // such a scope in the parent (since path() returns parent's path).
+  //
+  class temp_scope: public scope
+  {
+  public:
+    temp_scope (scope& p) {i_ = p.i_; parent_ = &p; root_ = p.root_;}
+  };
+
   class scope_map: public path_map<scope>
   {
   public: