private Type/*!*/ _underlyingSystemType; // the underlying CLI system type for this type

private string _name; // the name of the type

private Dictionary<string, PythonTypeSlot> _dict; // type-level slots & attributes

private PythonTypeAttributes _attrs; // attributes of the type

private int _flags; // CPython-like flags on the type

private int _version = GetNextVersion(); // version of the type

private List<WeakReference> _subtypes; // all of the subtypes of the PythonType

private PythonContext _pythonContext; // the context the type was created from, or null for system types.

private bool? _objectNew, _objectInit; // true if the type doesn't override __new__ / __init__ from object.

internal Dictionary<CachedGetKey, FastGetBase> _cachedGets; // cached gets on user defined type instances

internal Dictionary<CachedGetKey, FastGetBase> _cachedTryGets; // cached try gets on used defined type instances

internal Dictionary<SetMemberKey, FastSetBase> _cachedSets; // cached sets on user defined instances

internal Dictionary<string, TypeGetBase> _cachedTypeGets; // cached gets on types (system and user types)

internal Dictionary<string, TypeGetBase> _cachedTypeTryGets; // cached gets on types (system and user types)

// commonly calculatable

private List<PythonType> _resolutionOrder; // the search order for methods in the type

private PythonType/*!*/[]/*!*/ _bases; // the base classes of the type

private BuiltinFunction _ctor; // the built-in function which allocates an instance - a .NET ctor

private Type _finalSystemType; // base .NET type if we're inherited from another Python-like type.

// fields that frequently remain null

private WeakRefTracker _weakrefTracker; // storage for Python style weak references

private WeakReference _weakRef; // single weak ref instance used for all user PythonTypes.

private string[] _slots; // the slots when the class was created

private int _originalSlotCount; // the number of slots when the type was created

private InstanceCreator _instanceCtor; // creates instances

private CallSite<Func<CallSite, object, int>> _hashSite;

private CallSite<Func<CallSite, object, object, bool>> _eqSite;

private CallSite<Func<CallSite, object, object, int>> _compareSite;

private Dictionary<CallSignature, LateBoundInitBinder> _lateBoundInitBinders;

private string[] _optimizedInstanceNames; // optimized names stored in a custom dictionary

private int _optimizedInstanceVersion;

private Dictionary<string, List<MethodInfo>> _extensionMethods; // extension methods defined on the type

private PythonSiteCache _siteCache = new PythonSiteCache();

private PythonTypeSlot _lenSlot; // cached length slot, cleared when the type is mutated

internal Func<string, Exception, Exception> _makeException = DefaultMakeException;

[MultiRuntimeAware]

private static int MasterVersion = 1;

private static readonly CommonDictionaryStorage _pythonTypes = new CommonDictionaryStorage();

internal static readonly PythonType _pythonTypeType = DynamicHelpers.GetPythonTypeFromType(typeof(PythonType));

private static readonly WeakReference[] _emptyWeakRef = new WeakReference[0];

private static object _subtypesLock = new object();

internal static readonly Func<string, Exception, Exception> DefaultMakeException = (message, innerException) => new Exception(message, innerException);

internal static readonly Func<string, Exception> DefaultMakeExceptionNoInnerException = (message) => new Exception(message);

/// <summary>

/// Provides delegates that will invoke a parameterless type ctor. The first key provides

/// the dictionary for a specific type, the 2nd key provides the delegate for a specific

/// call site type used in conjunction w/ our IFastInvokable implementation.

/// </summary>

private static Dictionary<Type, Dictionary<Type, Delegate>> _fastBindCtors = new Dictionary<Type, Dictionary<Type, Delegate>>();

/// <summary>

/// Shared built-in functions for creating instances of user defined types. Because all

/// types w/ the same UnderlyingSystemType share the same constructors these can be

/// shared across multiple types.

/// </summary>

private static Dictionary<Type, BuiltinFunction> _userTypeCtors = new Dictionary<Type, BuiltinFunction>();

/// <summary>

/// Creates a new type for a user defined type. The name, base classes (a tuple of type

/// objects), and a dictionary of members is provided.

/// </summary>

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]

public PythonType(CodeContext/*!*/ context, string name, PythonTuple bases, PythonDictionary dict)

: this(context, name, bases, dict, String.Empty) {

}

/// <summary>

/// Creates a new type for a user defined type. The name, base classes (a tuple of type

/// objects), and a dictionary of members is provided.

/// </summary>

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]

internal PythonType(CodeContext/*!*/ context, string name, PythonTuple bases, PythonDictionary dict, string selfNames) {

InitializeUserType(context, name, bases, dict, selfNames);

}

internal PythonType() {

}

/// <summary>

/// Creates a new PythonType object which is backed by the specified .NET type for

/// storage. The type is considered a system type which can not be modified

/// by the user.

/// </summary>

/// <param name="underlyingSystemType"></param>

internal PythonType(Type underlyingSystemType) {

_underlyingSystemType = underlyingSystemType;

InitializeSystemType();

}

/// <summary>

/// Creates a new PythonType which is a subclass of the specified PythonType.

///

/// Used for runtime defined new-style classes which require multiple inheritance. The

/// primary example of this is the exception system.

/// </summary>

internal PythonType(PythonType baseType, string name, Func<string, Exception, Exception> exceptionMaker) {

_underlyingSystemType = baseType.UnderlyingSystemType;

IsSystemType = baseType.IsSystemType;

IsPythonType = baseType.IsPythonType;

Name = name;

_bases = new PythonType[] { baseType };

ResolutionOrder = Mro.Calculate(this, _bases);

_attrs |= PythonTypeAttributes.HasDictionary;

_makeException = exceptionMaker;

}

/// <summary>

/// Creates a new PythonType which is a subclass of the specified PythonTypes.

///

/// Used for runtime defined new-style classes which require multiple inheritance. The

/// primary example of this is the exception system.

/// </summary>

internal PythonType(PythonType[] baseTypes, string name) {

bool isSystemType = false;

bool isPythonType = false;

foreach (PythonType baseType in baseTypes) {

isSystemType |= baseType.IsSystemType;

isPythonType |= baseType.IsPythonType;

}

IsSystemType = isSystemType;

IsPythonType = isPythonType;

Name = name;

_bases = baseTypes;

ResolutionOrder = Mro.Calculate(this, _bases);

_attrs |= PythonTypeAttributes.HasDictionary;

}

/// <summary>

/// Creates a new PythonType which is a subclass of the specified PythonTypes.

///

/// Used for runtime defined new-style classes which require multiple inheritance. The

/// primary example of this is the exception system.

/// </summary>

internal PythonType(PythonType[] baseTypes, Type underlyingType, string name, Func<string, Exception, Exception> exceptionMaker)

: this(baseTypes, name) {

_underlyingSystemType = underlyingType;

_makeException = exceptionMaker;

}

/// <summary>

/// Creates a new PythonType which is a subclass of the specified PythonType.

///

/// Used for runtime defined new-style classes which require multiple inheritance. The

/// primary example of this is the exception system.

/// </summary>

internal PythonType(PythonContext context, PythonType baseType, string name, string module, string doc, Func<string, Exception, Exception> exceptionMaker)

: this(baseType, name, exceptionMaker) {

EnsureDict();

_dict["__doc__"] = new PythonTypeUserDescriptorSlot(doc, true);

_dict["__module__"] = new PythonTypeUserDescriptorSlot(module, true);

IsSystemType = false;

IsPythonType = false;

_pythonContext = context;

_attrs |= PythonTypeAttributes.HasDictionary;

}

/// <summary>

/// Creates a new PythonType which is a subclass of the specified PythonTypes.

///

/// Used for runtime defined new-style classes which require multiple inheritance. The

/// primary example of this is the exception system.

/// </summary>

internal PythonType(PythonContext context, PythonType[] baseTypes, string name, string module, string doc)

: this(baseTypes, name) {

EnsureDict();

_dict["__doc__"] = new PythonTypeUserDescriptorSlot(doc, true);

_dict["__module__"] = new PythonTypeUserDescriptorSlot(module, true);

_pythonContext = context;

_attrs |= PythonTypeAttributes.HasDictionary;

}

/// <summary>

/// Creates a new PythonType which is a subclass of the specified PythonTypes.

///

/// Used for runtime defined new-style classes which require multiple inheritance. The

/// primary example of this is the exception system.

/// </summary>

internal PythonType(PythonContext context, PythonType[] baseTypes, Type underlyingType, string name, string module, string doc, Func<string, Exception, Exception> exceptionMaker)

: this(baseTypes, underlyingType, name, exceptionMaker) {

EnsureDict();

_dict["__doc__"] = new PythonTypeUserDescriptorSlot(doc, true);

_dict["__module__"] = new PythonTypeUserDescriptorSlot(module, true);

IsSystemType = false;

IsPythonType = false;

_pythonContext = context;

_attrs |= PythonTypeAttributes.HasDictionary;

}

internal BuiltinFunction Ctor {

get {

EnsureConstructor();

return _ctor;

}

}

#region Public API

public static object __new__(CodeContext/*!*/ context, PythonType cls, string name, PythonTuple bases, PythonDictionary dict) {

return __new__(context, cls, name, bases, dict, String.Empty);

}

internal static object __new__(CodeContext/*!*/ context, PythonType cls, string name, PythonTuple bases, PythonDictionary dict, string selfNames) {

if (name == null) {

throw PythonOps.TypeError("type() argument 1 must be string, not None");

}

if (bases == null) {

throw PythonOps.TypeError("type() argument 2 must be tuple, not None");

}

if (dict == null) {

throw PythonOps.TypeError("TypeError: type() argument 3 must be dict, not None");

}

EnsureModule(context, dict);

PythonType meta = FindMetaClass(cls, bases);

if (meta != TypeCache.PythonType) {

object classdict = PythonOps.CallPrepare(context, meta, name, bases, dict);

if (meta != cls) {

// the user has a custom __new__ which picked the wrong meta class, call the correct metaclass

return PythonCalls.Call(context, meta, name, bases, classdict);

}

// we have the right user __new__, call our ctor method which will do the actual

// creation.

return meta.CreateInstance(context, name, bases, classdict);

}

// no custom user type for __new__

return new PythonType(context, name, bases, dict, selfNames);

}

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic")]

public void __init__(string name, PythonTuple bases, PythonDictionary dict) {

}

internal static PythonType FindMetaClass(PythonType cls, PythonTuple bases) {

PythonType meta = cls;

foreach (object dt in bases) {

PythonType metaCls = DynamicHelpers.GetPythonType(dt);

if (meta.IsSubclassOf(metaCls)) continue;

if (metaCls.IsSubclassOf(meta)) {

meta = metaCls;

continue;

}

throw PythonOps.TypeError("metaclass conflict: the metaclass of a derived class must be a (non-strict) subclass of the metaclasses of all its bases");

}

return meta;

}

public static object __new__(CodeContext/*!*/ context, object cls, object o) {

return DynamicHelpers.GetPythonType(o);

}

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic")]

public void __init__(object o) {

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static PythonTuple Get__bases__(CodeContext/*!*/ context, PythonType/*!*/ type) {

return type.GetBasesTuple();

}

private PythonTuple GetBasesTuple() {

object[] res = new object[BaseTypes.Count];

IList<PythonType> bases = BaseTypes;

for (int i = 0; i < bases.Count; i++) {

PythonType baseType = bases[i];

res[i] = baseType;

}

return PythonTuple.MakeTuple(res);

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static PythonType Get__base__(CodeContext/*!*/ context, PythonType/*!*/ type) {

foreach (object typeObj in Get__bases__(context, type)) {

if (typeObj is PythonType pt) {

return pt;

}

}

return null;

}

/// <summary>

/// Used in copyreg which is the only consumer of __flags__ in the standard library.

///

/// Set if the type is user defined

/// </summary>

private const int TypeFlagHeapType = 0x00000200;

/// <summary>

/// Set if the type has __abstractmethods__ defined

/// </summary>

private const int TypeFlagAbstractMethodsDefined = 0x00080000;

private const int TypeFlagAbstractMethodsNonEmpty = 0x00100000;

private bool SetAbstractMethodFlags(string name, object value) {

if (name != "__abstractmethods__") {

return false;

}

int res = _flags | TypeFlagAbstractMethodsDefined;

IEnumerator enumerator;

if (value == null ||

!PythonOps.TryGetEnumerator(DefaultContext.Default, value, out enumerator) ||

!enumerator.MoveNext()) {

// CPython treats None, non-iterables, and empty iterables as empty sets

// of abstract methods, and sets this flag accordingly

res &= ~(TypeFlagAbstractMethodsNonEmpty);

} else {

res |= TypeFlagAbstractMethodsNonEmpty;

}

_flags = res;

return true;

}

/// <summary>

/// Check whether the current type is iterable

/// </summary>

/// <param name="context"></param>

/// <returns>True if it is iterable</returns>

internal bool IsIterable(CodeContext context) {

object _dummy = null;

if (PythonOps.TryGetBoundAttr(context, this, "__iter__", out _dummy) &&

!Object.ReferenceEquals(_dummy, NotImplementedType.Value)

&& PythonOps.TryGetBoundAttr(context, this, "__next__", out _dummy) &&

!Object.ReferenceEquals(_dummy, NotImplementedType.Value))

{

return true;

}

return false;

}

private void ClearAbstractMethodFlags(string name) {

if (name == "__abstractmethods__") {

_flags &= ~(TypeFlagAbstractMethodsDefined | TypeFlagAbstractMethodsNonEmpty);

}

}

internal bool HasAbstractMethods(CodeContext/*!*/ context) {

object abstractMethods;

IEnumerator en;

return (_flags & TypeFlagAbstractMethodsNonEmpty) != 0 &&

TryGetBoundCustomMember(context, "__abstractmethods__", out abstractMethods) &&

PythonOps.TryGetEnumerator(context, abstractMethods, out en) &&

en.MoveNext();

}

internal string GetAbstractErrorMessage(CodeContext/*!*/ context) {

if ((_flags & TypeFlagAbstractMethodsNonEmpty) == 0) {

return null;

}

object abstractMethods;

IEnumerator en;

if (!TryGetBoundCustomMember(context, "__abstractmethods__", out abstractMethods) ||

!PythonOps.TryGetEnumerator(context, abstractMethods, out en) ||

!en.MoveNext()) {

return null;

}

string comma = "";

StringBuilder error = new StringBuilder("Can't instantiate abstract class ");

error.Append(Name);

error.Append(" with abstract methods ");

int i = 0;

do {

string s = en.Current as string;

if (s == null) {

if (en.Current is Extensible<string> es) {

s = es.Value;

}

}

if (s == null) {

return string.Format(

"sequence item {0}: expected string, {1} found",

i, PythonTypeOps.GetName(en.Current)

);

}

error.Append(comma);

error.Append(en.Current);

comma = ", ";

i++;

} while (en.MoveNext());

return error.ToString();

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static int Get__flags__(CodeContext/*!*/ context, PythonType/*!*/ type) {

int res = type._flags;

if (type.IsSystemType) {

res |= TypeFlagHeapType;

}

return res;

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static void Set__bases__(CodeContext/*!*/ context, PythonType/*!*/ type, object value) {

// validate we got a tuple...

if (!(value is PythonTuple t)) throw PythonOps.TypeError("expected tuple of types or old-classes, got '{0}'", PythonTypeOps.GetName(value));

List<PythonType> ldt = new List<PythonType>();

foreach (object o in t) {

// gather all the type objects...

if (!(o is PythonType adt)) {

throw PythonOps.TypeError("expected tuple of types, got '{0}'", PythonTypeOps.GetName(o));

}

ldt.Add(adt);

}

#if FEATURE_REFEMIT

// Ensure that we are not switching the CLI type

Type newType = NewTypeMaker.GetNewType(type.Name, t);

if (type.UnderlyingSystemType != newType)

throw PythonOps.TypeErrorForIncompatibleObjectLayout("__bases__ assignment", type, newType);

#endif

// set bases & the new resolution order

List<PythonType> mro = CalculateMro(type, ldt);

type.BaseTypes = ldt;

type._resolutionOrder = mro;

}

private static List<PythonType> CalculateMro(PythonType type, IList<PythonType> ldt) {

return Mro.Calculate(type, ldt);

}

private static bool TryReplaceExtensibleWithBase(Type curType, out Type newType) {

if (curType.IsGenericType &&

curType.GetGenericTypeDefinition() == typeof(Extensible<>)) {

newType = curType.GetGenericArguments()[0];

return true;

}

newType = null;

return false;

}

public object __call__(CodeContext context, params object[] args) {

return PythonTypeOps.CallParams(context, this, args);

}

public object __call__(CodeContext context, [ParamDictionary]IDictionary<string, object> kwArgs, params object[] args) {

return PythonTypeOps.CallWorker(context, this, kwArgs, args);

}

public int __cmp__([NotNull]PythonType other) {

if (other != this) {

int res = Name.CompareTo(other.Name);

if (res == 0) {

long thisId = IdDispenser.GetId(this);

long otherId = IdDispenser.GetId(other);

if (thisId > otherId) {

return 1;

}

return -1;

}

return res;

}

return 0;

}

// Do not override == and != because it causes lots of spurious warnings

// TODO Replace those warnings with .ReferenceEquals calls & overload ==/!=

public bool __eq__([NotNull]PythonType other) {

return __cmp__(other) == 0;

}

public bool __ne__([NotNull]PythonType other) {

return this.__cmp__(other) != 0;

}

[Python3Warning("type inequality comparisons not supported in 3.x")]

public static bool operator >(PythonType self, PythonType other) {

return self.__cmp__(other) > 0;

}

[Python3Warning("type inequality comparisons not supported in 3.x")]

public static bool operator <(PythonType self, PythonType other) {

return self.__cmp__(other) < 0;

}

[Python3Warning("type inequality comparisons not supported in 3.x")]

public static bool operator >=(PythonType self, PythonType other) {

return self.__cmp__(other) >= 0;

}

[Python3Warning("type inequality comparisons not supported in 3.x")]

public static bool operator <=(PythonType self, PythonType other) {

return self.__cmp__(other) <= 0;

}

public void __delattr__(CodeContext/*!*/ context, string name) {

DeleteCustomMember(context, name);

}

[SlotField]

public static PythonTypeSlot __dict__ = new PythonTypeDictSlot(_pythonTypeType);

[SpecialName, PropertyMethod, WrapperDescriptor]

public static object Get__doc__(CodeContext/*!*/ context, PythonType self) {

PythonTypeSlot pts;

object res;

if (self.TryLookupSlot(context, "__doc__", out pts) &&

pts.TryGetValue(context, null, self, out res)) {

return res;

} else if (self.IsSystemType) {

return PythonTypeOps.GetDocumentation(self.UnderlyingSystemType);

}

return null;

}

public object __getattribute__(CodeContext/*!*/ context, string name) {

object value;

if (TryGetBoundCustomMember(context, name, out value)) {

return value;

}

throw PythonOps.AttributeError("type object '{0}' has no attribute '{1}'", Name, name);

}

public PythonType this[params Type[] args] {

get {

if (UnderlyingSystemType == typeof(Array)) {

if (args.Length == 1) {

return DynamicHelpers.GetPythonTypeFromType(args[0].MakeArrayType());

}

throw PythonOps.TypeError("expected one argument to make array type, got {0}", args.Length);

}

if (!UnderlyingSystemType.IsGenericTypeDefinition) {

throw new InvalidOperationException("MakeGenericType on non-generic type");

}

return DynamicHelpers.GetPythonTypeFromType(UnderlyingSystemType.MakeGenericType(args));

}

}

public object this[string member] {

get {

if (!UnderlyingSystemType.IsEnum) {

throw PythonOps.TypeError("'type' object is not subscriptable");

}

if (member == null) {

throw PythonOps.KeyError(member);

}

try {

return Enum.Parse(UnderlyingSystemType, member);

} catch (ArgumentException) {

throw PythonOps.KeyError(member);

}

}

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static object Get__module__(CodeContext/*!*/ context, PythonType self) {

PythonTypeSlot pts;

object res;

if (self._dict != null &&

self._dict.TryGetValue("__module__", out pts) &&

pts.TryGetValue(context, self, DynamicHelpers.GetPythonType(self), out res)) {

return res;

}

return PythonTypeOps.GetModuleName(context, self.UnderlyingSystemType);

}

[SpecialName, PropertyMethod, WrapperDescriptor, PythonHidden]

public static string Get__clr_assembly__(PythonType self) {

return self.UnderlyingSystemType.Namespace + " in " + self.UnderlyingSystemType.Assembly.FullName;

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static void Set__module__(CodeContext/*!*/ context, PythonType self, object value) {

if (self.IsSystemType) {

throw PythonOps.TypeError("can't set {0}.__module__", self.Name);

}

Debug.Assert(self._dict != null);

self._dict["__module__"] = new PythonTypeUserDescriptorSlot(value);

self.UpdateVersion();

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static void Delete__module__(CodeContext/*!*/ context, PythonType self) {

throw PythonOps.TypeError("can't delete {0}.__module__", self.Name);

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static PythonTuple Get__mro__(PythonType type) {

return PythonTypeOps.MroToPython(type.ResolutionOrder);

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static string Get__name__(PythonType type) {

return type.Name;

}

[SpecialName, PropertyMethod, WrapperDescriptor]

public static void Set__name__(PythonType type, string name) {

if (type.IsSystemType) {

throw PythonOps.TypeError("can't set attributes of built-in/extension type '{0}'", type.Name);

}

type.Name = name;

}

public string/*!*/ __repr__(CodeContext/*!*/ context) {

string name = Name;

if (IsSystemType) {

if (PythonTypeOps.IsRuntimeAssembly(UnderlyingSystemType.Assembly) || IsPythonType) {

object module = Get__module__(context, this);

if (!module.Equals("builtins")) {

return string.Format("<class '{0}.{1}'>", module, Name);

}

}

return string.Format("<class '{0}'>", Name);

} else {

PythonTypeSlot dts;

string module = "unknown";

object modObj;

if (TryLookupSlot(context, "__module__", out dts) &&

dts.TryGetValue(context, this, this, out modObj)) {

module = modObj as string;

}

return string.Format("<class '{0}.{1}'>", module, name);

}

}

internal string/*!*/ GetTypeDebuggerDisplay() {

PythonTypeSlot dts;

string module = "unknown";

object modObj;

if (TryLookupSlot(Context.SharedContext, "__module__", out dts) &&

dts.TryGetValue(Context.SharedContext, this, this, out modObj)) {

module = modObj as string;

}

return string.Format("{0}.{1} instance", module, Name);

}

public void __setattr__(CodeContext/*!*/ context, string name, object value) {

SetCustomMember(context, name, value);

}

public PythonList __subclasses__(CodeContext/*!*/ context) {

PythonList ret = new PythonList();

IList<WeakReference> subtypes = SubTypes;

if (subtypes != null) {

PythonContext pc = context.LanguageContext;

foreach (WeakReference wr in subtypes) {

if (wr.IsAlive) {

PythonType pt = (PythonType)wr.Target;

if (pt.PythonContext == null || pt.PythonContext == pc) {

ret.AddNoLock(wr.Target);

}

}

}

}

return ret;

}

public virtual PythonList mro() {

return new PythonList(Get__mro__(this));

}

/// <summary>

/// Returns true if the specified object is an instance of this type.

/// </summary>

public virtual bool __instancecheck__(object instance) {

return SubclassImpl(DynamicHelpers.GetPythonType(instance));

}

public virtual bool __subclasscheck__(PythonType sub) {

return SubclassImpl(sub);

}

private bool SubclassImpl(PythonType sub) {

if (UnderlyingSystemType.IsInterface) {

// interfaces aren't in bases, and therefore IsSubclassOf doesn't do this check.

if (UnderlyingSystemType.IsAssignableFrom(sub.UnderlyingSystemType)) {

return true;

}

}

return sub.IsSubclassOf(this);

}

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2225:OperatorOverloadsHaveNamedAlternates")]

public static implicit operator Type(PythonType self) {

return self.UnderlyingSystemType;

}

public static implicit operator TypeTracker(PythonType self) {

return TypeTracker.GetTypeTracker(self.UnderlyingSystemType);

}

#endregion

#region Internal API

internal int SlotCount {

get {

return _originalSlotCount;

}

}

/// <summary>

/// Gets the name of the dynamic type

/// </summary>

internal string Name {

get {

return _name;

}

set {

_name = value;

}

}

internal int Version {

get {

return _version;

}

}

internal bool IsNull {

get {

return UnderlyingSystemType == typeof(DynamicNull);

}

}

/// <summary>

/// Gets the resolution order used for attribute lookup

/// </summary>

internal IList<PythonType> ResolutionOrder {

get {

return _resolutionOrder;

}

set {

lock (SyncRoot) {