public virtual Node LookupTypeOrNamespace(Identifier identifier, bool typeOnly, NamespaceScope nsScope, out TypeNodeList duplicates){
duplicates = null;
if (identifier == null || nsScope == null){Debug.Assert(false); return null;}
TypeNode t = nsScope.GetType(identifier, out duplicates, true);
if (t != null && t.Name != null && t.Name.UniqueIdKey == identifier.UniqueIdKey){
AliasDefinition aliasDef = nsScope.GetConflictingAlias(identifier);
if (aliasDef != null) aliasDef.ConflictingType = t;
}else if (!typeOnly){
TrivialHashtable alreadySeenAliases = new TrivialHashtable();
AliasDefinition aliasDef = nsScope.GetAliasFor(identifier);
while (aliasDef != null){
if (aliasDef.AliasedType != null) return (TypeNode)aliasDef.AliasedType;
if (alreadySeenAliases[aliasDef.UniqueKey] != null) break; //TODO: error?
alreadySeenAliases[aliasDef.UniqueKey] = aliasDef;
if (aliasDef.AliasedAssemblies != null) return aliasDef;
if (aliasDef.AliasedExpression is Identifier)
aliasDef = nsScope.GetAliasFor(identifier = (Identifier)aliasDef.AliasedExpression);
else if (aliasDef.AliasedExpression is QualifiedIdentifier)
return this.LookupTypeOrNamespace(aliasDef.AliasedExpression, false);
else
aliasDef = null;
}
Identifier ns = nsScope.GetNamespaceFullNameFor(identifier);
if (ns != null) return ns;
}
return t;
}