1 files changed, 25 insertions, 22 deletions
diff --git a/build/variable b/build/variable
index 0cd411d..42f0787 100644
--- a/build/variable
+++ b/build/variable
@@ -14,9 +14,10 @@
 #include <typeindex>
 #include <unordered_set>
 
+#include <butl/prefix-map>
+
 #include <build/path>
 #include <build/name>
-#include <build/prefix-map>
 
 namespace build
 {
@@ -207,24 +208,10 @@ namespace std
   };
 }
 
-namespace build
+namespace butl
 {
-  // variable_pool
-  //
-  struct variable_set: std::unordered_set<variable>
-  {
-    // @@ Need to check/set type?
-    //
-    const variable&
-    find (std::string name) {return *emplace (std::move (name)).first;}
-  };
-
-  extern variable_set variable_pool;
-
-  // variable_map
-  //
   template <>
-  struct compare_prefix<variable_cref>: compare_prefix<std::string>
+  struct compare_prefix<build::variable_cref>: compare_prefix<std::string>
   {
     typedef compare_prefix<std::string> base;
 
@@ -232,22 +219,38 @@ namespace build
     compare_prefix (char d): base (d) {}
 
     bool
-    operator() (const variable& x, const variable& y) const
+    operator() (const build::variable& x, const build::variable& y) const
     {
       return base::operator() (x.name, y.name);
     }
 
     bool
-    prefix (const variable& p, const variable& k) const
+    prefix (const build::variable& p, const build::variable& k) const
     {
       return base::prefix (p.name, k.name);
     }
   };
+}
 
-  struct variable_map: prefix_map<variable_cref, value_ptr, '.'>
+namespace build
+{
+  // variable_pool
+  //
+  struct variable_set: std::unordered_set<variable>
   {
-    typedef prefix_map<variable_cref, value_ptr, '.'> base;
+    // @@ Need to check/set type?
+    //
+    const variable&
+    find (std::string name) {return *emplace (std::move (name)).first;}
+  };
+
+  extern variable_set variable_pool;
 
+  // variable_map
+  //
+  using variable_map_base = butl::prefix_map<variable_cref, value_ptr, '.'>;
+  struct variable_map: variable_map_base
+  {
     value_proxy
     operator[] (const variable& var) const
     {
@@ -268,7 +271,7 @@ namespace build
     value_proxy
     assign (const variable& var)
     {
-      return value_proxy (&base::operator[] (var), this);
+      return value_proxy (&variable_map_base::operator[] (var), this);
     }
 
     value_proxy