private async Task <DynValue> ExecuteStatementList(List <AstNode> statements, CancellationToken token)
{
var retVal = DynValue.Zero;
if (BreakExecution)
{
BreakExecution = false;
throw new ScriptTerminationException("Execution stopped by user.");
}
foreach (var statement in statements)
{
do
{
token.ThrowIfCancellationRequested();
} while (SuspendExecution);
if (BreakExecution)
{
BreakExecution = false;
throw new ScriptTerminationException("Execution stopped by user.");
}
if (LoopStack.Count > 0)
{
var loopStackTop = LoopStack.Peek();
if (loopStackTop.BreakLoop || loopStackTop.SkipThisIteration)
{
break;
}
}
if (CallStack.Count > 0)
{
var callStackTop = CallStack.Peek();
if (callStackTop.ReturnNow)
{
retVal = callStackTop.ReturnValue;
break;
}
}
retVal = Visit(statement);
}
return(retVal);
}
public override DynValue Visit(ForLoopNode forLoopNode)
{
_ = Visit(forLoopNode.Assignment).Number;
DynValue step = new DynValue(1);
var targetValue = Visit(forLoopNode.TargetValue);
if (forLoopNode.Step != null)
{
step = Visit(forLoopNode.Step);
}
var isLocalScope = false;
var assignmentNode = (forLoopNode.Assignment as AssignmentNode);
var iteratorName = assignmentNode.Variable.Name;
if (assignmentNode.LocalScope)
{
isLocalScope = true;
}
try
{
LoopStack.Push(new LoopStackItem());
while (true)
{
ExecuteStatementList(forLoopNode.StatementList).GetAwaiter().GetResult();
double iterator;
if (isLocalScope)
{
var callStackTop = CallStack.Peek();
iterator = callStackTop.LocalVariableScope[iteratorName].Number;
}
else
{
iterator = Environment.Globals[iteratorName].Number;
}
if (step.Number < 0)
{
if (iterator < targetValue.Number)
{
break;
}
else
{
iterator -= step.Number;
}
}
else
{
if (iterator >= targetValue.Number)
{
break;
}
else
{
iterator += step.Number;
}
}
if (isLocalScope)
{
// no throw on localvar token, so
// guaranteed we're inside a function
var callStackTop = CallStack.Peek();
callStackTop.LocalVariableScope[iteratorName] = new DynValue(iterator);
}
else
{
Environment.Globals[iteratorName] = new DynValue(iterator);
}
var loopStackTop = LoopStack.Peek();
if (loopStackTop.BreakLoop)
{
break;
}
if (loopStackTop.SkipThisIteration)
{
loopStackTop.SkipThisIteration = false;
continue;
}
}
}
catch
{
throw;
}
finally
{
LoopStack.Pop();
}
return(DynValue.Zero);
}