#if NETCOREAPP2_0 || NETCOREAPP2_1

public static readonly bool IsNetCoreApp = true;

#else

public static readonly bool IsNetCoreApp = false;

#endif

public static string TargetFramework => typeof(ClrModule).Assembly.GetCustomAttribute<TargetFrameworkAttribute>()?.FrameworkName;

#if DEBUG

public static readonly bool IsDebug = true;

#else

public static readonly bool IsDebug = false;

#endif

private static int _isMono = -1;

public static bool IsMono {

get {

if(_isMono == -1) {

_isMono = Type.GetType ("Mono.Runtime") != null ? 1 : 0;

}

return _isMono == 1;

}

}

[SpecialName]

public static void PerformModuleReload(PythonContext/*!*/ context, PythonDictionary/*!*/ dict) {

if (!dict.ContainsKey("References")) {

dict["References"] = context.ReferencedAssemblies;

}

}

#region Public methods

/// <summary>

/// Gets the current ScriptDomainManager that IronPython is loaded into. The

/// ScriptDomainManager can then be used to work with the language portion of the

/// DLR hosting APIs.

/// </summary>

public static ScriptDomainManager/*!*/ GetCurrentRuntime(CodeContext/*!*/ context) {

return context.LanguageContext.DomainManager;

}

[Documentation(@"Adds a reference to a .NET assembly. Parameters can be an already loaded

public static void AddReference(CodeContext/*!*/ context, params object[] references) {

if (references == null) throw new TypeErrorException("Expected string or Assembly, got NoneType");

if (references.Length == 0) throw new ValueErrorException("Expected at least one name, got none");

ContractUtils.RequiresNotNull(context, "context");

foreach (object reference in references) {

AddReference(context, reference);

}

}

[Documentation(@"Adds a reference to a .NET assembly. One or more assembly names can

public static void AddReferenceToFile(CodeContext/*!*/ context, params string[] files) {

if (files == null) throw new TypeErrorException("Expected string, got NoneType");

if (files.Length == 0) throw new ValueErrorException("Expected at least one name, got none");

ContractUtils.RequiresNotNull(context, "context");

foreach (string file in files) {

AddReferenceToFile(context, file);

}

}

[Documentation(@"Adds a reference to a .NET assembly. Parameters are an assembly name.

public static void AddReferenceByName(CodeContext/*!*/ context, params string[] names) {

if (names == null) throw new TypeErrorException("Expected string, got NoneType");

if (names.Length == 0) throw new ValueErrorException("Expected at least one name, got none");

ContractUtils.RequiresNotNull(context, "context");

foreach (string name in names) {

AddReferenceByName(context, name);

}

}

#if FEATURE_LOADWITHPARTIALNAME

[Documentation(@"Adds a reference to a .NET assembly. Parameters are a partial assembly name.

public static void AddReferenceByPartialName(CodeContext/*!*/ context, params string[] names) {

if (names == null) throw new TypeErrorException("Expected string, got NoneType");

if (names.Length == 0) throw new ValueErrorException("Expected at least one name, got none");

ContractUtils.RequiresNotNull(context, "context");

foreach (string name in names) {

AddReferenceByPartialName(context, name);

}

}

#endif

#if FEATURE_FILESYSTEM

[Documentation(@"Adds a reference to a .NET assembly. Parameters are a full path to an.

public static Assembly/*!*/ LoadAssemblyFromFileWithPath(CodeContext/*!*/ context, string/*!*/ file) {

if (file == null) throw new TypeErrorException("LoadAssemblyFromFileWithPath: arg 1 must be a string.");

Assembly res;

if (!context.LanguageContext.TryLoadAssemblyFromFileWithPath(file, out res)) {

if (!Path.IsPathRooted(file)) {

throw new ValueErrorException("LoadAssemblyFromFileWithPath: path must be rooted");

} else if (!File.Exists(file)) {

throw new ValueErrorException("LoadAssemblyFromFileWithPath: file not found");

} else {

throw new ValueErrorException("LoadAssemblyFromFileWithPath: error loading assembly");

}

}

return res;

}

[Documentation(@"Loads an assembly from the specified filename and returns the assembly

public static Assembly/*!*/ LoadAssemblyFromFile(CodeContext/*!*/ context, string/*!*/ file) {

if (file == null) throw new TypeErrorException("Expected string, got NoneType");

if (file.Length == 0) throw new ValueErrorException("assembly name must not be empty string");

ContractUtils.RequiresNotNull(context, "context");

if (file.IndexOf(System.IO.Path.DirectorySeparatorChar) != -1) {

throw new ValueErrorException("filenames must not contain full paths, first add the path to sys.path");

}

return context.LanguageContext.LoadAssemblyFromFile(file);

}

#endif

#if FEATURE_LOADWITHPARTIALNAME

[Documentation(@"Loads an assembly from the specified partial assembly name and returns the

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Reliability", "CA2001:AvoidCallingProblematicMethods", MessageId = "System.Reflection.Assembly.LoadWithPartialName")]

public static Assembly/*!*/ LoadAssemblyByPartialName(string/*!*/ name) {

if (name == null) {

throw new TypeErrorException("LoadAssemblyByPartialName: arg 1 must be a string");

}

#pragma warning disable 618, 612 // csc

return Assembly.LoadWithPartialName(name);

#pragma warning restore 618, 612

}

#endif

[Documentation(@"Loads an assembly from the specified assembly name and returns the assembly

public static Assembly/*!*/ LoadAssemblyByName(CodeContext/*!*/ context, string/*!*/ name) {

if (name == null) {

throw new TypeErrorException("LoadAssemblyByName: arg 1 must be a string");

}

return context.LanguageContext.DomainManager.Platform.LoadAssembly(name);

}

/// <summary>

/// Use(name) -> module

///

/// Attempts to load the specified module searching all languages in the loaded ScriptRuntime.

/// </summary>

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

ContractUtils.RequiresNotNull(context, "context");

if (name == null) {

throw new TypeErrorException("Use: arg 1 must be a string");

}

var scope = Importer.TryImportSourceFile(context.LanguageContext, name);

if (scope == null) {

throw new ValueErrorException(String.Format("couldn't find module {0} to use", name));

}

return scope;

}

[Documentation("Converts an array of bytes to a string.")]

public static string GetString(byte[] bytes) {

return GetString(bytes, bytes.Length);

}

[Documentation("Converts maxCount of an array of bytes to a string")]

public static string GetString(byte[] bytes, int maxCount) {

int bytesToCopy = Math.Min(bytes.Length, maxCount);

return Encoding.GetEncoding("iso-8859-1").GetString(bytes, 0, bytesToCopy);

}

[Documentation("Converts a string to an array of bytes")]

public static byte[] GetBytes(string s) {

return GetBytes(s, s.Length);

}

[Documentation("Converts maxCount of a string to an array of bytes")]

public static byte[] GetBytes(string s, int maxCount) {

int charsToCopy = Math.Min(s.Length, maxCount);

byte[] ret = new byte[charsToCopy];

Encoding.GetEncoding("iso-8859-1").GetBytes(s, 0, charsToCopy, ret, 0);

return ret;

}

/// <summary>

/// Use(path, language) -> module

///

/// Attempts to load the specified module belonging to a specific language loaded into the

/// current ScriptRuntime.

/// </summary>

public static object/*!*/ Use(CodeContext/*!*/ context, string/*!*/ path, string/*!*/ language) {

ContractUtils.RequiresNotNull(context, "context");

if (path == null) {

throw new TypeErrorException("Use: arg 1 must be a string");

}

if (language == null) {

throw new TypeErrorException("Use: arg 2 must be a string");

}

var manager = context.LanguageContext.DomainManager;

if (!manager.Platform.FileExists(path)) {

throw new ValueErrorException(String.Format("couldn't load module at path '{0}' in language '{1}'", path, language));

}

var sourceUnit = manager.GetLanguageByName(language).CreateFileUnit(path);

return Importer.ExecuteSourceUnit(context.LanguageContext, sourceUnit);

}

/// <summary>

/// SetCommandDispatcher(commandDispatcher)

///

/// Sets the current command dispatcher for the Python command line.

///

/// The command dispatcher will be called with a delegate to be executed. The command dispatcher

/// should invoke the target delegate in the desired context.

///

/// A common use for this is to enable running all REPL commands on the UI thread while the REPL

/// continues to run on a non-UI thread.

/// </summary>

public static Action<Action> SetCommandDispatcher(CodeContext/*!*/ context, Action<Action> dispatcher) {

ContractUtils.RequiresNotNull(context, "context");

return ((PythonContext)context.LanguageContext).GetSetCommandDispatcher(dispatcher);

}

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

if (type == null) {

throw PythonOps.TypeError("type must not be None");

} else if (!type.IsSystemType) {

throw PythonOps.ValueError("type must be .NET type");

}

lock (context.ModuleContext) {

context.ModuleContext.ExtensionMethods = ExtensionMethodSet.AddType(context.LanguageContext, context.ModuleContext.ExtensionMethods, type);

}

}

public static void ImportExtensions(CodeContext/*!*/ context, [NotNull]NamespaceTracker @namespace) {

lock (context.ModuleContext) {

context.ModuleContext.ExtensionMethods = ExtensionMethodSet.AddNamespace(context.LanguageContext, context.ModuleContext.ExtensionMethods, @namespace);

}

}

#if FEATURE_COM

/// <summary>

/// LoadTypeLibrary(rcw) -> type lib desc

///

/// Gets an ITypeLib object from OLE Automation compatible RCW ,

/// reads definitions of CoClass'es and Enum's from this library

/// and creates an object that allows to instantiate coclasses

/// and get actual values for the enums.

/// </summary>

public static ComTypeLibInfo LoadTypeLibrary(CodeContext/*!*/ context, object rcw) {

return ComTypeLibDesc.CreateFromObject(rcw);

}

/// <summary>

/// LoadTypeLibrary(guid) -> type lib desc

///

/// Reads the latest registered type library for the corresponding GUID,

/// reads definitions of CoClass'es and Enum's from this library

/// and creates a IDynamicMetaObjectProvider that allows to instantiate coclasses

/// and get actual values for the enums.

/// </summary>

public static ComTypeLibInfo LoadTypeLibrary(CodeContext/*!*/ context, Guid typeLibGuid) {

return ComTypeLibDesc.CreateFromGuid(typeLibGuid);

}

/// <summary>

/// AddReferenceToTypeLibrary(rcw) -> None

///

/// Makes the type lib desc available for importing. See also LoadTypeLibrary.

/// </summary>

public static void AddReferenceToTypeLibrary(CodeContext/*!*/ context, object rcw) {

ComTypeLibInfo typeLibInfo;

typeLibInfo = ComTypeLibDesc.CreateFromObject(rcw);

PublishTypeLibDesc(context, typeLibInfo.TypeLibDesc);

}

/// <summary>

/// AddReferenceToTypeLibrary(guid) -> None

///

/// Makes the type lib desc available for importing. See also LoadTypeLibrary.

/// </summary>

public static void AddReferenceToTypeLibrary(CodeContext/*!*/ context, Guid typeLibGuid) {

ComTypeLibInfo typeLibInfo;

typeLibInfo = ComTypeLibDesc.CreateFromGuid(typeLibGuid);

PublishTypeLibDesc(context, typeLibInfo.TypeLibDesc);

}

private static void PublishTypeLibDesc(CodeContext context, ComTypeLibDesc typeLibDesc) {

PythonOps.ScopeSetMember(context, context.LanguageContext.DomainManager.Globals, typeLibDesc.Name, typeLibDesc);

}

#endif

#endregion

#region Private implementation methods

private static void AddReference(CodeContext/*!*/ context, object reference) {

Assembly asmRef = reference as Assembly;

if (asmRef != null) {

AddReference(context, asmRef);

return;

}

string strRef = reference as string;

if (strRef != null) {

AddReference(context, strRef);

return;

}

throw new TypeErrorException(String.Format("Invalid assembly type. Expected string or Assembly, got {0}.", reference));

}

private static void AddReference(CodeContext/*!*/ context, Assembly assembly) {

context.LanguageContext.DomainManager.LoadAssembly(assembly);

}

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes")] // TODO: fix

private static void AddReference(CodeContext/*!*/ context, string name) {

if (name == null) throw new TypeErrorException("Expected string, got NoneType");

Assembly asm = null;

try {

asm = LoadAssemblyByName(context, name);

} catch { }

// note we don't explicit call to get the file version

// here because the assembly resolve event will do it for us.

#if FEATURE_LOADWITHPARTIALNAME

if (asm == null) {

asm = LoadAssemblyByPartialName(name);

}

#endif

if (asm == null) {

throw new IOException(String.Format("Could not add reference to assembly {0}", name));

}

AddReference(context, asm);

}

private static void AddReferenceToFile(CodeContext/*!*/ context, string file) {

if (file == null) throw new TypeErrorException("Expected string, got NoneType");

#if FEATURE_FILESYSTEM

Assembly asm = LoadAssemblyFromFile(context, file);

#else

Assembly asm = context.LanguageContext.DomainManager.Platform.LoadAssemblyFromPath(file);

#endif

if (asm == null) {

throw new IOException(String.Format("Could not add reference to assembly {0}", file));

}

AddReference(context, asm);

}

#if FEATURE_LOADWITHPARTIALNAME

private static void AddReferenceByPartialName(CodeContext/*!*/ context, string name) {

if (name == null) throw new TypeErrorException("Expected string, got NoneType");

ContractUtils.RequiresNotNull(context, "context");

Assembly asm = LoadAssemblyByPartialName(name);

if (asm == null) {

throw new IOException(String.Format("Could not add reference to assembly {0}", name));

}

AddReference(context, asm);

}

#endif

private static void AddReferenceByName(CodeContext/*!*/ context, string name) {

if (name == null) throw new TypeErrorException("Expected string, got NoneType");

Assembly asm = LoadAssemblyByName(context, name);

if (asm == null) {

throw new IOException(String.Format("Could not add reference to assembly {0}", name));

}

AddReference(context, asm);

}

#endregion

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1034:NestedTypesShouldNotBeVisible")] // TODO: fix

public sealed class ReferencesList : List<Assembly>, ICodeFormattable {

public new void Add(Assembly other) {

base.Add(other);

}

[System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Design", "CA1002:DoNotExposeGenericLists"), SpecialName]

public ClrModule.ReferencesList Add(object other) {

IEnumerator ie = PythonOps.GetEnumerator(other);

while (ie.MoveNext()) {

Assembly cur = ie.Current as Assembly;

if (cur == null) throw PythonOps.TypeError("non-assembly added to references list");

base.Add(cur);

}

return this;

}

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

StringBuilder res = new StringBuilder("(");

string comma = "";

foreach (Assembly asm in this) {

res.Append(comma);

res.Append('<');

res.Append(asm.FullName);

res.Append('>');

comma = "," + Environment.NewLine;

}

res.AppendLine(")");

return res.ToString();

}

}

private static PythonType _strongBoxType;

#region Runtime Type Checking support

#if FEATURE_FILESYSTEM

[Documentation(@"Adds a reference to a .NET assembly. One or more assembly names can

public static void AddReferenceToFileAndPath(CodeContext/*!*/ context, params string[] files) {

if (files == null) throw new TypeErrorException("Expected string, got NoneType");

ContractUtils.RequiresNotNull(context, "context");

foreach (string file in files) {

AddReferenceToFileAndPath(context, file);

}

}

private static void AddReferenceToFileAndPath(CodeContext/*!*/ context, string file) {

if (file == null) throw PythonOps.TypeError("Expected string, got NoneType");

// update our path w/ the path of this file...

string path = System.IO.Path.GetDirectoryName(Path.GetFullPath(file));

List list;

PythonContext pc = context.LanguageContext;

if (!pc.TryGetSystemPath(out list)) {

throw PythonOps.TypeError("cannot update path, it is not a list");

}

list.append(path);

Assembly asm = pc.LoadAssemblyFromFile(file);

if (asm == null) throw PythonOps.IOError("file does not exist: {0}", file);

AddReference(context, asm);

}

#endif

/// <summary>

/// Gets the CLR Type object from a given Python type object.

/// </summary>

public static Type GetClrType(Type type) {

return type;

}

/// <summary>

/// Gets the Python type object from a given CLR Type object.

/// </summary>

public static PythonType GetPythonType(Type t) {

return DynamicHelpers.GetPythonTypeFromType(t);

}

/// <summary>

/// OBSOLETE: Gets the Python type object from a given CLR Type object.

///

/// Use clr.GetPythonType instead.

/// </summary>

[Obsolete("Call clr.GetPythonType instead")]

public static PythonType GetDynamicType(Type t) {

return DynamicHelpers.GetPythonTypeFromType(t);

}

public static PythonType Reference {

get {

return StrongBox;

}

}

public static PythonType StrongBox {

get {

if (_strongBoxType == null) {

_strongBoxType = DynamicHelpers.GetPythonTypeFromType(typeof(StrongBox<>));

}

return _strongBoxType;

}

}

/// <summary>

/// accepts(*types) -> ArgChecker

///

/// Decorator that returns a new callable object which will validate the arguments are of the specified types.

/// </summary>

/// <param name="types"></param>

/// <returns></returns>

public static object accepts(params object[] types) {

return new ArgChecker(types);

}

/// <summary>

/// returns(type) -> ReturnChecker

///

/// Returns a new callable object which will validate the return type is of the specified type.

/// </summary>

public static object returns(object type) {

return new ReturnChecker(type);

}

public static object Self() {

return null;

}

#endregion

/// <summary>

/// Decorator for verifying the arguments to a function are of a specified type.

/// </summary>

public class ArgChecker {

private object[] expected;

public ArgChecker(object[] prms) {

expected = prms;

}

#region ICallableWithCodeContext Members

[SpecialName]

public object Call(CodeContext context, object func) {

// expect only to receive the function we'll call here.

return new RuntimeArgChecker(func, expected);

}

#endregion

}

/// <summary>

/// Returned value when using clr.accepts/ArgChecker. Validates the argument types and

/// then calls the original function.

/// </summary>

public class RuntimeArgChecker : PythonTypeSlot {

private object[] _expected;

private object _func;

private object _inst;

public RuntimeArgChecker(object function, object[] expectedArgs) {

_expected = expectedArgs;

_func = function;

}

public RuntimeArgChecker(object instance, object function, object[] expectedArgs)

: this(function, expectedArgs) {

_inst = instance;

}

private void ValidateArgs(object[] args) {

int start = 0;

if (_inst != null) {

start = 1;

}

// no need to validate self... the method should handle it.

for (int i = start; i < args.Length + start; i++) {

PythonType dt = DynamicHelpers.GetPythonType(args[i - start]);

PythonType expct = _expected[i] as PythonType;

if (expct == null) expct = ((OldClass)_expected[i]).TypeObject;

if (dt != _expected[i] && !dt.IsSubclassOf(expct)) {

throw PythonOps.AssertionError("argument {0} has bad value (got {1}, expected {2})", i, dt, _expected[i]);

}

}

}

#region ICallableWithCodeContext Members

[SpecialName]

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

ValidateArgs(args);

if (_inst != null) {

return PythonOps.CallWithContext(context, _func, ArrayUtils.Insert(_inst, args));

} else {

return PythonOps.CallWithContext(context, _func, args);

}

}

#endregion

internal override bool TryGetValue(CodeContext context, object instance, PythonType owner, out object value) {

value = new RuntimeArgChecker(instance, _func, _expected);

return true;

}

internal override bool GetAlwaysSucceeds {

get {

return true;

}

}

#region IFancyCallable Members

[SpecialName]

public object Call(CodeContext context, [ParamDictionary]IDictionary<object, object> dict, params object[] args) {

ValidateArgs(args);

if (_inst != null) {

return PythonCalls.CallWithKeywordArgs(context, _func, ArrayUtils.Insert(_inst, args), dict);

} else {

return PythonCalls.CallWithKeywordArgs(context, _func, args, dict);

}

}

#endregion

}

/// <summary>

/// Decorator for verifying the return type of functions.

/// </summary>

public class ReturnChecker {

public object retType;

public ReturnChecker(object returnType) {

retType = returnType;

}

#region ICallableWithCodeContext Members

[SpecialName]

public object Call(CodeContext context, object func) {

// expect only to receive the function we'll call here.

return new RuntimeReturnChecker(func, retType);

}

#endregion

}

/// <summary>

/// Returned value when using clr.returns/ReturnChecker. Calls the original function and

/// validates the return type is of a specified type.

/// </summary>

public class RuntimeReturnChecker : PythonTypeSlot {

private object _retType;

private object _func;

private object _inst;

public RuntimeReturnChecker(object function, object expectedReturn) {

_retType = expectedReturn;

_func = function;

}

public RuntimeReturnChecker(object instance, object function, object expectedReturn)

: this(function, expectedReturn) {

_inst = instance;

}

private void ValidateReturn(object ret) {

// we return void...

if (ret == null && _retType == null) return;

PythonType dt = DynamicHelpers.GetPythonType(ret);

if (dt != _retType) {

PythonType expct = _retType as PythonType;

if (expct == null) expct = ((OldClass)_retType).TypeObject;

if (!dt.IsSubclassOf(expct))

throw PythonOps.AssertionError("bad return value returned (expected {0}, got {1})", _retType, dt);

}

}

#region ICallableWithCodeContext Members

[SpecialName]

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

object ret;

if (_inst != null) {

ret = PythonOps.CallWithContext(context, _func, ArrayUtils.Insert(_inst, args));

} else {

ret = PythonOps.CallWithContext(context, _func, args);

}

ValidateReturn(ret);

return ret;

}

#endregion

#region IDescriptor Members

public object GetAttribute(object instance, object owner) {

return new RuntimeReturnChecker(instance, _func, _retType);

}

#endregion

internal override bool TryGetValue(CodeContext context, object instance, PythonType owner, out object value) {

value = GetAttribute(instance, owner);

return true;

}

internal override bool GetAlwaysSucceeds {

get {

return true;

}

}

#region IFancyCallable Members

[SpecialName]

public object Call(CodeContext context, [ParamDictionary]IDictionary<object, object> dict, params object[] args) {

object ret;

if (_inst != null) {

ret = PythonCalls.CallWithKeywordArgs(context, _func, ArrayUtils.Insert(_inst, args), dict);

} else {

return PythonCalls.CallWithKeywordArgs(context, _func, args, dict);

}

ValidateReturn(ret);

return ret;

}

#endregion

}

/// <summary>

/// returns the result of dir(o) as-if "import clr" has not been performed.

/// </summary>

public static List Dir(object o) {

IList<object> ret = PythonOps.GetAttrNames(DefaultContext.Default, o);

List lret = new List(ret);

lret.sort(DefaultContext.Default);

return lret;

}

/// <summary>

/// Returns the result of dir(o) as-if "import clr" has been performed.

/// </summary>

public static List DirClr(object o) {

IList<object> ret = PythonOps.GetAttrNames(DefaultContext.DefaultCLS, o);

List lret = new List(ret);

lret.sort(DefaultContext.DefaultCLS);

return lret;

}

/// <summary>

/// Attempts to convert the provided object to the specified type. Conversions that

/// will be attempted include standard Python conversions as well as .NET implicit

/// and explicit conversions.

///

/// If the conversion cannot be performed a TypeError will be raised.

/// </summary>

public static object Convert(CodeContext/*!*/ context, object o, Type toType) {

return Converter.Convert(o, toType);

}

#if FEATURE_FILESYSTEM && FEATURE_REFEMIT

/// <summary>

/// Provides a helper for compiling a group of modules into a single assembly. The assembly can later be

/// reloaded using the clr.AddReference API.

/// </summary>

public static void CompileModules(CodeContext/*!*/ context, string/*!*/ assemblyName, [ParamDictionary]IDictionary<string, object> kwArgs, params string/*!*/[]/*!*/ filenames) {

ContractUtils.RequiresNotNull(assemblyName, "assemblyName");

ContractUtils.RequiresNotNullItems(filenames, "filenames");

PythonContext pc = context.LanguageContext;

for (int i = 0; i < filenames.Length; i++) {

filenames[i] = Path.GetFullPath(filenames[i]);

}

Dictionary<string, string> packageMap = BuildPackageMap(filenames);

List<SavableScriptCode> code = new List<SavableScriptCode>();

foreach (string filename in filenames) {

if (!pc.DomainManager.Platform.FileExists(filename)) {