diff --git a/include/xo/expression2/StringTable.hpp b/include/xo/expression2/StringTable.hpp
index b55c48ee..8d0354c8 100644
--- a/include/xo/expression2/StringTable.hpp
+++ b/include/xo/expression2/StringTable.hpp
@@ -21,7 +21,7 @@ namespace xo {
         class StringTable {
         public:
             using DArena = xo::mm::DArena;
-            using MemorySizeInfo = xo::mm::MemorySizeInfo;
+            using MemorySizeVisitor = xo::mm::MemorySizeVisitor;
             using StringMap = xo::map::DArenaHashMap<std::string_view,
                                                      DUniqueString*>;
             using size_type = StringMap::size_type;
@@ -46,8 +46,8 @@ namespace xo {
              **/
             bool verify_ok(verify_policy p = verify_policy::throw_only()) const;
 
-            std::size_t _n_store() const noexcept;
-            MemorySizeInfo _store_info(std::size_t i) const noexcept;
+            /** visit string-table memory pools, call visitor(info) for each **/
+            void visit_pools(const MemorySizeVisitor & visitor) const;
 
         private:
             /** allocate string storage in this arena; use DString to represent each string.
diff --git a/src/expression2/StringTable.cpp b/src/expression2/StringTable.cpp
index 79a17067..174c9e9f 100644
--- a/src/expression2/StringTable.cpp
+++ b/src/expression2/StringTable.cpp
@@ -160,22 +160,11 @@ namespace xo {
             return true;
         }
 
-        std::size_t
-        StringTable::_n_store() const noexcept
+        void
+        StringTable::visit_pools(const MemorySizeVisitor & visitor) const
         {
-            return 1 + map_._n_store();
-        }
-
-        MemorySizeInfo
-        StringTable::_store_info(std::size_t i) const noexcept
-        {
-            if (i == 0) 
-                return strings_._store_info();
-                
-            if (i+1 < map_._n_store())
-                return map_._store_info(i-1);
-
-            return MemorySizeInfo::sentinel();
+            strings_.visit_pools(visitor);
+            map_.visit_pools(visitor);
         }
 
     } /*namespace scm*/