Cell* search_symbol(string s, bool expected)
{
//stack<symbol_map> temp_AR_stack;
symbol_map curr_map;
symbol_map::iterator curr_map_it;
bool exist = false;
Cell* linked_symbol = NULL;
/* while (!(AR_stack.empty()))
{
curr_map = AR_stack.top();
curr_map_it = curr_map.find(s);
// Check if the current record (map) has the mapped value
if (curr_map_it != curr_map.end())
{
linked_symbol = curr_map_it->second;
exist = true;
break;
}
else
{
temp_AR_stack.push(curr_map);
AR_stack.pop();
}
}
*/
for (int i = AR_vector.size()-1; i>=0; i--)
{
curr_map = AR_vector[i];
curr_map_it = curr_map.find(s);
//Check if the current record (map) contains the mapped value
if (curr_map_it != curr_map.end())
{
linked_symbol = curr_map_it->second;
exist = true;
break;
}
}
/*
* after searching the symbol map, if it is still not found,
* check the global variable record
*/
if (!exist)
{
SMap_it = SMap.find(s);
if ((SMap_it == SMap.end())&&expected)
{
//if (!Symbol_operator_finder(s))
throw runtime_error("attempt to reference an undefined symbol \"" + s
+"\"");
//return make_symbol(s.c_str());
}
else if (SMap_it == SMap.end())
linked_symbol = NULL;
else
linked_symbol = SMap_it->second;
}
return linked_symbol;
}
void insert_element(string s, Cell* map_cell)
{
//check if there is any local symbol table
if (!(AR_vector.empty()))
{
symbol_map curr_map = AR_vector.back();
AR_vector.pop_back();
symbol_map::iterator curr_map_it = curr_map.find(s);
//check if it is defined before
if (curr_map_it != curr_map.end())
{
AR_vector.push_back(curr_map);
throw runtime_error(s + " cannot be redefined.");
}
curr_map[s] = map_cell;
AR_vector.push_back(curr_map);
}
else
{
SMap_it = SMap.find(s);
//check if it is defined before
if (SMap_it != SMap.end())
throw runtime_error(s + " cannot be redefined.");
SMap.insert( pair< string, Cell*>(s,map_cell));
}
}