Minor optimizations to parser (use const string& for ids, keep only one binding in symtab)

1 files changed, 13 insertions, 7 deletions

diff --git a/src/parser/symbol_table.h b/src/parser/symbol_table.h
index dd110c4c1..1f43dbda6 100644
--- a/src/parser/symbol_table.h
+++ b/src/parser/symbol_table.h
@@ -42,8 +42,12 @@ class SymbolTable {
 private:
 
   /** The name to expression bindings */
+  typedef __gnu_cxx::hash_map<std::string, ObjectType>
+  LookupTable;
+/*
   typedef __gnu_cxx::hash_map<std::string, std::stack<ObjectType> >
   LookupTable;
+*/
   /** The table iterator */
   typedef typename LookupTable::iterator table_iterator;
   /** The table iterator */
@@ -58,21 +62,23 @@ public:
    * Bind the name of the variable to the given expression. If the variable
    * has been bind before, this will redefine it until its undefined.
    */
-  void bindName(const std::string name, const ObjectType& obj) throw () {
-    d_nameBindings[name].push(obj);
+  void bindName(const std::string& name, const ObjectType& obj) throw () {
+    d_nameBindings[name] = obj;
     Assert(isBound(name), "Expected name to be bound!");
   }
 
   /**
    * Unbinds the last binding of the name to the expression.
    */
-  void unbindName(const std::string name) throw () {
+  void unbindName(const std::string& name) throw () {
     table_iterator find = d_nameBindings.find(name);
     if(find != d_nameBindings.end()) {
+/*
       find->second.pop();
       if(find->second.empty()) {
+*/
         d_nameBindings.erase(find);
-      }
+/*      }*/
     }
   }
 
@@ -80,16 +86,16 @@ public:
    * Returns the last binding expression of the name.
    * Requires the name to have a binding in the table.
    */
-  ObjectType getObject(const std::string name) throw () {
+  ObjectType getObject(const std::string& name) throw () {
     table_iterator find = d_nameBindings.find(name);
     Assert(find != d_nameBindings.end());
-    return find->second.top();
+    return find->second /*.top()*/ ;
   }
 
   /**
    * Returns true is name is bound to an expression.
    */
-  bool isBound(const std::string name) const throw () {
+  bool isBound(const std::string& name) const throw () {
     const_table_iterator find = d_nameBindings.find(name);
     return (find != d_nameBindings.end());
   }