1. Tag at C++ Compiler
Kei Hasegawa

2. scope : Symbol Table struct scope { }; scope* m_parent;
vector<scope*> m_children;
map<string, vector<usr*> > m_usrs; // Variable etc
map<string, tag*> m_tags; // Structure etc
...
virtual ~scope(); };

3. tag : expressing structure etc
// C Compiler
struct tag {
// Scope where the structure is declared
scope* m_scope;
... };
// C++ Compiler
struct tag : scope {
// scope::m_parent is correspond to m_scope of C Compiler
... };

4. Destroy symbol tables when finishing to compile a function definition
// C Compiler
void destroy_temporary() {
...
// Simple!
vector<scope*>& children = scope::root.m_children;
for (auto p : children)
delete p;
children.clear(); }

5. Destroy symbol tables when finishing to compile a function definition(2)
// C++ Compiler
void destroy_temporary() {
...
vector<scope*>& children = scope::root.m_children;
for (IT p = begin(children) ; p != end(children) ; ) {
switch ( (*p)->m_id) {
case PARAM: case BLOCK:
delete *p;
p = children.erase(p);
break;
default:
++p; // Not delete structure or namespace }

6. scope::~scope() // C Compiler scope::~scope() { }
for (auto p : m_children)
delete p;
...
for (auto& p : m_tags)
p.second->m_scope = 0; // Not understandable. See C Compiler Temporary Type Document. }

7. scope::~scope() (2) // C++ Compiler scope::~scope() {
for (auto p : m_children) {
switch (p->m_id) {
case PARAM: case BLOCK: delete p; break;
default: p->m_parent = 0; // Break parent-child relation }
// Nothing to be done for `m_tags’