/// <summary>
/// Initializes a new instance of the EvaluateTimeBase class.
/// </summary>
/// <param name="expr">The expression to evaluate.</param>
/// <param name="count">The number of times to evaluate.</param>
/// <param name="env">The evaluation environment</param>
/// <param name="caller">The caller. Return to this when done.</param>
protected EvaluateTimeBase(SchemeObject expr, int count, Environment env, Evaluator caller)
: base(InitialStep, expr, env, caller)
{
this.counter = count;
this.startMem = GC.GetTotalMemory(true);
this.stopwatch = Stopwatch.StartNew();
}
/// <summary>
/// Initializes a new instance of the SynchronousClrProcedure class.
/// </summary>
/// <param name="targetClassName">The class of the object to invoke.</param>
/// <param name="methodName">The method to invoke.</param>
/// <param name="instanceClass">The type of the instance argument. Null if static or constructor.</param>
/// <param name="argClasses">The types of each argument.</param>
/// <param name="caller">The calling evaluator.</param>
private SynchronousClrProcedure(string targetClassName, string methodName, Type instanceClass, Type[] argClasses, Evaluator caller)
: base(targetClassName,
methodName,
GetMethodInfo(targetClassName, methodName, argClasses, caller),
instanceClass,
argClasses,
argClasses.Length)
{
}
/// <summary>
/// Execute the continuation.
/// Transfers execution to the evaluator saved when the continuation was created.
/// The environment in effect at that time is also restored.
/// Again, the chain of steps back to the beginning need to be clones so that this application
/// does not alter the evaluation, making it impossible to return back to the continuation.
/// </summary>
/// <param name="args">The value to return.</param>
/// <param name="env"></param>
/// <param name="returnTo">The evaluator to return to. This can be different from caller if this is the last step in evaluation</param>
/// <param name="caller">The calling evaluator. Not used, since control is transferred away.</param>
/// <returns>The next evaluator to execute.</returns>
internal override Evaluator Apply(SchemeObject args, Environment env, Evaluator returnTo, Evaluator caller)
{
#if Check
this.CheckArgCount(ListLength(args), args, "Continuation", caller);
#endif
Evaluator nextStep = this.savedEvaluator.CloneChain();
nextStep.ReturnedExpr = First(args);
nextStep.ReturnedEnv = this.savedEvaluator.Env;
return nextStep;
}
/// <summary>
/// Call the parallel evaluator.
/// </summary>
/// <param name="expr">The expressions to evaluate.</param>
/// <param name="env">The environment to evaluate in.</param>
/// <param name="caller">The caller. Return to this when done.</param>
/// <returns>The parallel evaluator.</returns>
internal static Evaluator Call(SchemeObject expr, Environment env, Evaluator caller)
{
if (expr is EmptyList)
{
caller = caller.Caller;
caller.ReturnedExpr = EmptyList.Instance;
return caller;
}
return new EvaluateParallel(expr, env, caller);
}
/// <summary>
/// Initializes a new instance of the AsynchronousClrProcedure class.
/// </summary>
/// <param name="targetClassName">The class name of the CLR function.</param>
/// <param name="methodName">The method name of the CLR function.</param>
/// <param name="instanceClass">The type of the instance argument. Null if static or constructor.</param>
/// <param name="argClasses">The types of all method arguments.</param>
/// <param name="caller">The calling evaluator.</param>
internal AsynchronousClrProcedure(string targetClassName, string methodName, Type instanceClass, Type[] argClasses, Evaluator caller)
: base(targetClassName,
methodName,
GetMethodInfo(targetClassName, "Begin" + methodName, argClasses, caller),
instanceClass,
argClasses,
argClasses.Length - 1)
{
var endClasses = new[] { typeof(IAsyncResult) };
this.endMethodInfo = GetMethodInfo(targetClassName, "End" + methodName, endClasses, caller);
}
/// <summary>
/// Closes the output port and returns the evaluation result.
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>The evaluation result.</returns>
private static Evaluator CloseStep(Evaluator s)
{
var step = (EvaluateCallWithOutputFile)s;
if (step.port != null)
{
step.port.Close();
}
Evaluator caller = step.Caller;
caller.ReturnedExpr = s.ReturnedExpr;
return caller;
}
/// <summary>
/// Back here after expression evaluation.
/// Increment and test the counter.
/// If not done, loop back.
/// Otherwise, calculate elapsed time and mem use.
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>Continue, or else give the timer results.</returns>
protected static Evaluator CompleteStep(Evaluator s)
{
var step = (EvaluateTimeBase)s;
step.i++;
if (step.i < step.counter)
{
s.Pc = EvaluateStep;
return s;
}
step.stopwatch.Stop();
long time = step.stopwatch.ElapsedMilliseconds;
long mem = GC.GetTotalMemory(false) - step.startMem;
Evaluator caller = step.Caller;
caller.ReturnedExpr =
MakeList(
s.ReturnedExpr,
MakeList((Number)time, (Symbol)"msec"),
MakeList((Number)mem, (Symbol)"bytes"));
return caller;
}
/// <summary>
/// Initializes a new instance of the Interpreter class.
/// Create an interpreter and install the primitives into the global environment.
/// Then read a list of files.
/// </summary>
/// <param name="loadStandardMacros">Load standard macros and other primitives.</param>
/// <param name="primEnvironment">Environment containing the primitives (can be null).</param>
/// <param name="files">The files to read.</param>
/// <param name="reader">The input reader.</param>
/// <param name="writer">The output writer.</param>
private Interpreter(
bool loadStandardMacros,
PrimitiveEnvironment primEnvironment,
IEnumerable<string> files,
TextReader reader,
TextWriter writer)
{
this.Trace = false;
this.Count = false;
this.Transcript = new TranscriptLogger(this);
this.CurrentInputPort = InputPort.New(reader ?? Console.In, this);
this.CurrentOutputPort = OutputPort.New(writer ?? Console.Out, this);
this.PrimEnvironment = primEnvironment ?? new PrimitiveEnvironment();
this.CurrentCounters = new Counter();
this.GlobalEnvironment = new Environment(this, this.PrimEnvironment);
this.halted = new HaltedEvaluator(this.GlobalEnvironment);
var echo = (writer != null) ? this.CurrentOutputPort : null;
try
{
if (loadStandardMacros)
{
this.Load(SchemePrimitives.Code);
}
if (files != null)
{
foreach (string file in files)
{
this.LoadFile((Symbol)file, echo);
}
}
}
catch (Exception ex)
{
ErrorHandlers.PrintException(ex);
}
}
/// <summary>
/// Initializes a new instance of the EvaluateExpression class.
/// At this point, fn is something that evaluates to a proc.
/// It might be a symbol that, when looked up, resolves to a primitive or to a
/// proc of some kind, like a lambda.
/// It is not a symbol like "and" where there are special argument-evaluation rules, so
/// the first task is to evaluate all the arguments.
/// </summary>
/// <param name="fn">The function to evaluate (the expression in the first position).</param>
/// <param name="args">The function args to evaluate (the rest of the expressions in the list).</param>
/// <param name="env">The evaluation environment</param>
/// <param name="caller">The caller. Return to this when done.</param>
private EvaluateExpression(SchemeObject fn, SchemeObject args, Environment env, Evaluator caller)
: base(InitialStep, args, env, caller)
{
this.fn = fn;
if (fn is Symbol)
{
// If the fun is a symbol, we can avoid the first step.
this.Pc = ApplyProcStep;
Call(fn, env, this);
}
else if (fn is Procedure)
{
// Or if the fun is already a procedure, skip the first step.
this.Pc = ApplyProcStep;
this.ReturnedExpr = fn;
}
}
/// <summary>
/// Start by setting up timers and counter.
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>Continue to next step.</returns>
private static Evaluator InitialStep(Evaluator s)
{
var step = (EvaluateTimeBase)s;
step.i = 0;
s.Pc = EvaluateStep;
return s;
}
/// <summary>
/// Comes back here after evaluation completes synchronously or is suspended.
/// If evaluation is suspended, then EvaluateExpressionWithCatch will catch and return undefined.
/// Loop back and evaluate another expression.
/// Continue looping until all evaluations return an actual result.
/// Accumulate the results and return when everything finishes.
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>Immediately steps back.</returns>
private static Evaluator LoopStep(Evaluator s)
{
var step = (EvaluateParallel)s;
lock (step.lockObj)
{
step.FetchReturnValue();
switch (step.ReturnFlag)
{
case ReturnType.CaughtSuspended:
// caught an asynchronous suspension -- go on to the next expr
step.forked++;
break;
case ReturnType.AsynchronousReturn:
// return after suspension
// Record return result and either end the thread or
// return from the whole thing.
step.accum = Cons(step.ReturnedExpr, step.accum);
step.joined++;
if (step.joined < step.forked || !(s.Expr is EmptyList))
{
return new FinalEvaluator(Undefined.Instance);
}
Evaluator caller = step.Caller;
caller.ReturnedExpr = step.accum;
return caller;
case ReturnType.SynchronousReturn:
// synchronous return
step.accum = Cons(step.ReturnedExpr, step.accum);
break;
}
s.Expr = Rest(s.Expr);
if (s.Expr is EmptyList)
{
// finished with expressions -- either suspend (if there is more pending) or
// return from the whole thing
if (step.joined < step.forked)
{
s.Pc = LoopStep;
return new SuspendedEvaluator(s.ReturnedExpr, s).NextStep();
}
Evaluator caller = step.Caller;
caller.ReturnedExpr = step.accum;
return caller;
}
s.Pc = LoopStep;
return EvaluateExpressionWithCatch.Call(First(s.Expr), s.Env, s);
}
}
/// <summary>
/// Create an evaluator with output file.
/// </summary>
/// <param name="args">A pair, containing a filename and a proc to evaluate.</param>
/// <param name="caller">The caller. Return to this when done.</param>
/// <returns>The created evaluator.</returns>
internal static Evaluator Call(SchemeObject args, Evaluator caller)
{
OutputPort port = OpenOutputFile(First(args), caller.Interp);
return new EvaluateCallWithOutputFile(args, caller.Env, caller, port);
}
/// <summary>
/// Open the output file and apply the proc.
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>The next step in the application, or if the result is ready,
/// continues to the next step.</returns>
private static Evaluator InitialStep(Evaluator s)
{
var step = (EvaluateCallWithOutputFile)s;
var proc = Second(s.Expr);
s.Pc = CloseStep;
return ((Procedure)proc).Apply(MakeList(step.port), null, s, s);
}
/// <summary>
/// Initializes a new instance of the Continuation class.
/// The evaluator and its chain of evaluators back to the beginning have to be cloned because they
/// hold information about the progress of the evaluation. When the evaluation proceeds
/// these evaluators might be altered, damaging the ability to continue, which is what makes the
/// clone necessary.
/// </summary>
/// <param name="eval">The continuation to return to when applied.</param>
/// <returns>A new continuation.</returns>
public static Continuation New(Evaluator eval)
{
return new Continuation(eval);
}
/// <summary>
/// Take a list of CLR method arguments and turn them into an array, suitable for
/// calling the method.
/// Add the extra async arguments for the Begin call.
/// Check to make sure the number and types of the arguments in the list match
/// what is expected.
/// </summary>
/// <param name="args">A list of the method arguments.</param>
/// <param name="state">State, passed on to completion function.</param>
/// <param name="caller">The calling evaluator.</param>
/// <returns>An array of arguments for the method call.</returns>
private object[] ToArgListBegin(SchemeObject args, object state, Evaluator caller)
{
object[] additionalArgs = { (AsyncCallback)this.CompletionMethod, state };
return this.ToArgList(args, additionalArgs, "AsynchronousClrProcedure", caller);
}
/// <summary>
/// Take a list of CLR method arguments and turn them into a list, suitable for
/// calling the method.
/// Check to make sure the number and types of the arguments in the list match
/// what is expected.
/// </summary>
/// <param name="args">A list of the method arguments.</param>
/// <param name="additionalArgs">A list of the additional args, not supplied by the caller.
/// These are part of the asynchronous calling pattern.</param>
/// <param name="evaluatorName">The evaluator name, for the error message.</param>
/// <param name="caller">The calling evaluator.</param>
/// <returns>An array of arguments for the method call.</returns>
protected object[] ToArgList(SchemeObject args, object[] additionalArgs, string evaluatorName, Evaluator caller)
{
// This has been checked once already, in Procedure.CheckArgCount, but that included
// an instance argument. Check again to protect the rest of this method.
int additionalN = additionalArgs != null ? additionalArgs.Length : 0;
int numArgs = ListLength(args) + additionalN;
int expectedArgs = this.ArgClasses.Length;
if (numArgs != expectedArgs)
{
this.ArgCountError(numArgs, expectedArgs, args, evaluatorName, caller);
}
var array = new object[numArgs];
int a = 0;
while (args is Pair)
{
array[a] = ClrObject.ToClrObject(First(args), this.ArgClasses[a]);
a++;
args = Rest(args);
}
for (int i = 0; i < additionalN; i++)
{
Debug.Assert(additionalArgs != null, "ClrProcedure: additionalArgs != null");
array[a++] = additionalArgs[i];
}
return array;
}
/// <summary>
/// Look up the method info.
/// </summary>
/// <param name="className">The class name of the class to get method info about</param>
/// <param name="theMethodName">The method name</param>
/// <param name="argClassList">The argument types.</param>
/// <param name="caller">The calling evaluator.</param>
/// <returns>The method info for the method.</returns>
protected static MethodInfo GetMethodInfo(
string className,
string theMethodName,
Type[] argClassList,
Evaluator caller)
{
// TODO use caller to get line number
caller.FindLineNumberInCallStack();
try
{
Type cls = className.ToClass();
if (cls == null)
{
ErrorHandlers.ClrError(string.Format("Can't find class: {0} at line {1}", className, caller.FindLineNumberInCallStack()));
return null;
}
MethodInfo info = cls.GetMethod(theMethodName, argClassList);
if (info == null)
{
ErrorHandlers.ClrError(string.Format("Can't find method: {0}:{1} at line {2}", className, theMethodName, caller.FindLineNumberInCallStack()));
return null;
}
return info;
}
catch (TypeLoadException)
{
ErrorHandlers.ClrError(string.Format("Bad class, can't load: {0} at line {1}", className, caller.FindLineNumberInCallStack()));
return null;
}
}
/// <summary>
/// Execute the constructor.
/// Match all arguments supplied up to the constructor's types.
/// </summary>
/// <param name="args">Arguments to pass to the constructor.</param>
/// <param name="env">The environment of the evaluation.</param>
/// <param name="returnTo">The evaluator to return to. This can be different from caller if this is the last step in evaluation</param>
/// <param name="caller">The calling evaluator.</param>
/// <returns>The next evaluator to excute.</returns>
internal override Evaluator Apply(SchemeObject args, Environment env, Evaluator returnTo, Evaluator caller)
{
#if Check
this.CheckArgCount(ListLength(args), args, "ClrConstructor", caller);
#endif
Assembly assembly = this.classType.Assembly;
object[] argArray = this.ToArgList(args, null, "ClrConstructor", caller);
object res = assembly.CreateInstance(this.classType.FullName, false, BindingFlags.Default, null, argArray, null, null);
returnTo.ReturnedExpr = ClrObject.New(res);
return returnTo;
}
/// <summary>
/// Initial step: evaluate the first expression.
/// Instead of calling normal EvaluateExpression, call a variant that catches suspended
/// execution and halts the evaluation.
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>The next evaluator.</returns>
private static Evaluator InitialStep(Evaluator s)
{
s.Pc = LoopStep;
return EvaluateExpressionWithCatch.Call(First(s.Expr), s.Env, s);
}
/// <summary>
/// Apply the method to the given arguments.
/// If the method is static, all arguments are passed to the method.
/// Otherwise, the first argument is the class instance, and the rest are passed
/// to the method.
/// </summary>
/// <param name="args">Arguments to pass to the method.</param>
/// <param name="env">The environment of the application.</param>
/// <param name="returnTo">The evaluator to return to. This can be different from caller if this is the last step in evaluation</param>
/// <param name="caller">The calling evaluator.</param>
/// <returns>The next evaluator to excute.</returns>
internal override Evaluator Apply(SchemeObject args, Environment env, Evaluator returnTo, Evaluator caller)
{
SchemeObject target = null;
if (!this.MethodInfo.IsStatic)
{
target = First(args);
args = Rest(args);
}
#if Check
this.CheckArgCount(ListLength(args), args, "SynchronousClrProcedure", caller);
#endif
var actualTarget = ClrObject.ToClrObject(target, this.InstanceClass);
var argList = this.ToArgList(args, null, "SynchronousClrProcedure", caller);
object res = this.MethodInfo.Invoke(actualTarget, argList);
res = res ?? Undefined.Instance;
returnTo.ReturnedExpr = ClrObject.FromClrObject(res);
return returnTo;
}
/// <summary>
/// Exit the whole process.
/// </summary>
/// <param name="args">If given, the process exit code.</param>
/// <param name="caller">The calling evaluator (not used).</param>
/// <returns>Does not return.</returns>
private static SchemeObject Exit(SchemeObject args, Evaluator caller)
{
System.Environment.Exit(List.First(args) is EmptyList ? 0 : Number.AsInt(List.First(args)));
return Undefined.Instance;
}
/// <summary>
/// Subclass must provide an implementation.
/// This evaluates the expression, in a way that is appropriate
/// to the function (eval or apply).
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>The next step.</returns>
protected static Evaluator EvaluateStep(Evaluator s)
{
return ((EvaluateTimeBase)s).EvaluateStep();
}
/// <summary>
/// Initializes a new instance of the Continuation class.
/// The evaluator and its chain of evaluators back to the beginning have to be cloned because they
/// hold information about the progress of the evaluation. When the evaluation proceeds
/// these evaluators might be altered, damaging the ability to continue, which is what makes the
/// clone necessary.
/// </summary>
/// <param name="eval">The continuation to return to when applied.</param>
private Continuation(Evaluator eval)
: base(null, new ArgsInfo(1, 1, false))
{
this.savedEvaluator = eval.CloneChain();
}
/// <summary>
/// Increment the variable.
/// The intention is that this should be atomic.
/// Used by increment! primitive.
/// </summary>
/// <param name="expr">The symbol whose value is incremented.</param>
/// <param name="env">The environment.</param>
/// <param name="caller">Return to this caller.</param>
/// <returns>The next step to execute.</returns>
private static Evaluator Increment(SchemeObject expr, Environment env, Evaluator caller)
{
SchemeObject lhs = First(expr);
if (!(lhs is Symbol))
{
ErrorHandlers.SemanticError(string.Format(@"Increment: first argument must be a symbol. Got: ""{0}""", lhs), null);
}
caller.ReturnedExpr = env.Increment(lhs);
return caller;
}
/// <summary>
/// Start evaluation by testing the various forms.
/// The special forms have their own evaluators.
/// Otherwise, evaluate the first argument (the proc) in preparation for a call.
/// </summary>
/// <param name="s">This evaluator.</param>
/// <returns>The next thing to do.</returns>
private static Evaluator InitialStep(Evaluator s)
{
var step = (EvaluateExpression)s;
// If we get here, it wasn't one of the special forms.
// So we need to evaluate the first item (the function) in preparation for
// doing a procedure call.
//// <r4rs section="4.1.3">(<operator> <operand1> ...)</r4rs>
s.Pc = ApplyProcStep;
return Call(step.fn, s.Env, s);
}
/// <summary>
/// Apply the method to the given arguments.
/// If the method is static, all arguments are passed to the method.
/// Otherwise, the first argument is the class instance, and the rest are passed
/// to the method.
/// </summary>
/// <param name="args">Arguments to pass to the method.</param>
/// <param name="env">The environment of the application.</param>
/// <param name="returnTo">The evaluator to return to. This can be different from caller if this is the last step in evaluation</param>
/// <param name="caller">The calling evaluator.</param>
/// <returns>The next evaluator to execute.</returns>
internal override Evaluator Apply(SchemeObject args, Environment env, Evaluator returnTo, Evaluator caller)
{
#if Check
this.CheckArgCount(ListLength(args), args, "AsynchronousClrProcedure", caller);
#endif
SchemeObject target = null;
if (!this.MethodInfo.IsStatic)
{
target = First(args);
args = Rest(args);
}
var actualTarget = ClrObject.ToClrObject(target, this.InstanceClass);
var argArray = this.ToArgListBegin(args, new Tuple<object, Evaluator>(actualTarget, returnTo), caller);
var res = this.MethodInfo.Invoke(actualTarget, argArray) as IAsyncResult;
// res is not converted because it is IAsyncResult -- convert in completion method
return new SuspendedEvaluator(ClrObject.New(res), returnTo).NextStep();
}
/// <summary>
/// Initializes a new instance of the EvaluateCallWithOutputFile class.
/// </summary>
/// <param name="args">A pair, containing a filename and a proc to evaluate.</param>
/// <param name="env">The evaluation environment</param>
/// <param name="caller">The caller. Return to this when done.</param>
/// <param name="port">The output port.</param>
private EvaluateCallWithOutputFile(SchemeObject args, Environment env, Evaluator caller, OutputPort port)
: base(InitialStep, args, env, caller)
{
this.port = port;
}
/// <summary>
/// Perform steps until evaluation is complete or suspended.
/// Calling "a subroutine" does not recursively call EvalSteps.
/// A "call" is handled by creating a new evaluator and passing a step within it as the nextStep.
/// A "return" is handled by return a step in the "caller" as the next step.
/// </summary>
/// <param name="evaluator">The evaluator to execute first.</param>
/// <returns>The evaluation result, or suspended evaluator.</returns>
internal SchemeObject EvalSteps(Evaluator evaluator)
{
while (true)
{
// Get the PC from the evaluator and call the action it points to, passing it the evaluator instance.
evaluator = evaluator.Pc(evaluator);
if (evaluator.Finished)
{
return evaluator.ReturnedExpr;
}
}
}
/// <summary>
/// Evaluate a quote expression.
/// </summary>
/// <param name="args">The args to quote.</param>
/// <param name="env">The environment (unused).</param>
/// <param name="caller">The caller.</param>
/// <returns>The quoted expression.</returns>
private static Evaluator EvalQuote(SchemeObject args, Environment env, Evaluator caller)
{
caller.ReturnedExpr = First(args);
return caller;
}
/// <summary>
/// Initializes a new instance of the EvaluateParallel class.
/// </summary>
/// <param name="expr">The expressions to evaluate.</param>
/// <param name="env">The evaluation environment</param>
/// <param name="caller">The caller. Return to this when done.</param>
private EvaluateParallel(SchemeObject expr, Environment env, Evaluator caller)
: base(InitialStep, expr, env, caller)
{
this.forked = this.joined = 0;
this.accum = EmptyList.Instance;
}