AST idea

dllqueue.c

@@ -0,0 +1,55 @@
+function void
+push(Type *l, Type *node){
+  if(l->first == 0){
+    l->first = l->last = node;
+    node->prev = 0;
+    node->next = 0;
+  }
+  else{
+    l->last->next = node;
+    node->prev = l->last;
+    node->next = 0;
+    l->last = node;
+  }
+  node->parent = l;
+}
+
+function void
+push_front(Type *l, Type *node){
+  if(l->first == 0){
+    l->first = l->last = node;
+    node->prev = 0;
+    node->next = 0;
+  }
+  else{
+    node->next = l->first;
+    l->first->prev = node;
+    node->prev = 0;
+    l->first = node;
+  }
+  node->parent = l;
+}
+
+function void
+remove(Type *l, Type *node){
+  if(l->first == l->last){
+    assert(node == l->last);
+    l->first = l->last = 0;
+  }
+  else if(l->last == node){
+    l->last = l->last->prev;
+    l->last->next = 0;
+  }
+  else if(l->first == node){
+    l->first = l->first->next;
+    l->first->prev = 0;
+  }
+  else{
+    node->prev->next = node->next;
+    node->next->prev = node->prev;
+  }
+  
+  node->parent = 0;
+  node->prev = 0;
+  node->next = 0;
+}