+struct CYNonLocal;
+struct CYThisScope;
+
+struct CYContext {
+ CYOptions &options_;
+
+ CYScope *scope_;
+ CYThisScope *this_;
+
+ CYIdentifierUsageVector rename_;
+
+ CYNonLocal *nonlocal_;
+ CYNonLocal *nextlocal_;
+ unsigned unique_;
+
+ CYContext(CYOptions &options) :
+ options_(options),
+ scope_(NULL),
+ this_(NULL),
+ nonlocal_(NULL),
+ nextlocal_(NULL),
+ unique_(0)
+ {
+ }
+
+ virtual ~CYContext() {
+ }
+
+ template <typename Type_>
+ void ReplaceAll(Type_ *&values) {
+ Type_ **last(&values);
+ CYForEach (next, values) {
+ Replace(*last = next);
+ if (*last != NULL)
+ last = &(*last)->next_;
+ }
+ }
+
+ template <typename Type_>
+ void Replace(Type_ *&value) {
+ for (;;) if (value == NULL)
+ break;
+ else {
+ Type_ *replace(value->Replace(*this));
+ if (replace != value)
+ value = replace;
+ else break;
+ }
+ }
+
+ void NonLocal(CYStatement *&statements);
+ CYIdentifier *Unique();
+};
+
+struct CYNonLocal {
+ CYIdentifier *identifier_;
+
+ CYNonLocal() :
+ identifier_(NULL)
+ {
+ }
+
+ CYIdentifier *Target(CYContext &context) {
+ if (identifier_ == NULL)
+ identifier_ = context.Unique();
+ return identifier_;
+ }
+};
+
+struct CYThisScope :
+ CYNext<CYThisScope>
+{
+ CYIdentifier *identifier_;
+
+ CYThisScope() :
+ identifier_(NULL)
+ {
+ }
+
+ CYIdentifier *Identifier(CYContext &context) {
+ if (next_ != NULL)
+ return next_->Identifier(context);
+ if (identifier_ == NULL)
+ identifier_ = context.Unique();
+ return identifier_;
+ }
+};
+