Implement dist support for including/excluding targets

For example:

cxx{*-options}: dist = true

3 files changed, 19 insertions, 5 deletions

diff --git a/build/dist/module.cxx b/build/dist/module.cxx
index 0b60fa8..9bd058a 100644
--- a/build/dist/module.cxx
+++ b/build/dist/module.cxx
@@ -58,6 +58,8 @@ namespace build
       //
       if (first)
       {
+        variable_pool.find ("dist", bool_type);
+
         variable_pool.find ("dist.package", string_type);
 
         variable_pool.find ("dist.root", dir_path_type);
diff --git a/build/dist/operation.cxx b/build/dist/operation.cxx
index 0fb3aef..2a84894 100644
--- a/build/dist/operation.cxx
+++ b/build/dist/operation.cxx
@@ -199,6 +199,7 @@ namespace build
       // entered.
       //
       action_targets files;
+      const variable& dist_var (variable_pool.find ("dist"));
 
       for (const auto& pt: targets)
       {
@@ -211,7 +212,13 @@ namespace build
         {
           // Include unless explicitly excluded.
           //
-          files.push_back (ft);
+          auto l ((*ft)[dist_var]);
+
+          if (l && !as<bool> (*l))
+            level5 ([&]{trace << "excluding " << *ft;});
+          else
+            files.push_back (ft);
+
           continue;
         }
 
@@ -219,7 +226,14 @@ namespace build
         {
           // Exclude unless explicitly included.
           //
-          //files.push_back (*ft);
+          auto l ((*ft)[dist_var]);
+
+          if (l && as<bool> (*l))
+          {
+            level5 ([&]{trace << "including " << *ft;});
+            files.push_back (ft);
+          }
+
           continue;
         }
       }
diff --git a/build/dist/rule.cxx b/build/dist/rule.cxx
index 6977676..b5e1185 100644
--- a/build/dist/rule.cxx
+++ b/build/dist/rule.cxx
@@ -33,11 +33,9 @@ namespace build
         if (p.proj () != nullptr)
           continue;
 
-        // @@ This is where we will handle dist/nodist.
-
         target& pt (p.search ());
 
-        // Don't match targets that are outside our project.
+        // Don't match targets that are outside of our project.
         //
         if (pt.dir.sub (out_root))
           build::match (a, pt);