public NumericValueExpressionSegment(NumericValueToken token)
{
if (token == null)
{
throw new ArgumentNullException("token");
}
Token = token;
}
public ForNextLoopState(StatementMarker startMarker, VariableNameToken _variableNameToken, NumericValueToken _startValue,
NumericValueToken _endValue, NumericValueToken _stepValue)
{
LoopMarker = startMarker;
VariableNameToken = _variableNameToken;
StartValue = _startValue;
EndValue = _endValue;
StepValue = _stepValue;
CurrentValue = StartValue;
ImmediateModeStatementIndex = -1;
}
public ForNextLoopState(int _immediateModeStatementIndex, VariableNameToken _variableNameToken, NumericValueToken _startValue,
NumericValueToken _endValue, NumericValueToken _stepValue)
{
ImmediateModeStatementIndex = _immediateModeStatementIndex;
VariableNameToken = _variableNameToken;
StartValue = _startValue;
EndValue = _endValue;
StepValue = _stepValue;
CurrentValue = StartValue;
LoopMarker = null;
}
public override void Execute(Interpreter interpreter, TokenMarker tokenMarker)
{
if (!(tokenMarker.Token is VariableNameToken variableNameToken))
{
throw new Exceptions.SyntaxErrorException();
}
if (variableNameToken.VariableType != VariableValueType.RealNumber)
{
throw new Exceptions.SyntaxErrorException();
}
if (!(tokenMarker.GetNextToken() is EqualToken))
{
throw new Exceptions.SyntaxErrorException();
}
tokenMarker.MoveNext();
NumericValueToken startValue;
try
{
startValue = (NumericValueToken)interpreter.ExpressionEvaluator.Evaluate(tokenMarker);
}
catch (InvalidCastException)
{
throw new Exceptions.TypeMismatchException();
}
if (!(tokenMarker.Token is ToToken))
{
throw new Exceptions.SyntaxErrorException();
}
tokenMarker.MoveNext();
NumericValueToken endValue;
try
{
endValue = (NumericValueToken)interpreter.ExpressionEvaluator.Evaluate(tokenMarker);
}
catch (InvalidCastException)
{
throw new Exceptions.TypeMismatchException();
}
NumericValueToken stepValueToken = null;
if (tokenMarker.Token != null)
{
if (!(tokenMarker.Token is StepToken))
{
throw new Exceptions.SyntaxErrorException();
}
tokenMarker.MoveNext();
var result = interpreter.ExpressionEvaluator.Evaluate(tokenMarker);
if (!(result is NumericValueToken))
{
throw new Exceptions.TypeMismatchException();
}
stepValueToken = (NumericValueToken)result;
}
else
{
// Default step is 1 or -1
// if (startValue.RealValue <= endValue.RealValue)
stepValueToken = interpreter.TokensProvider.CreateRealValueToken(1);
// else
// stepValueToken = interpreter.TokensProvider.CreateRealValueToken(-1);
}
ForNextLoopState forNextLoopState;
if (interpreter.InterpreterMode == InterpreterMode.Running)
{
var forNextMarker = interpreter.CopyCurrentStatementMarker();
// In immediate mode, FOR may not neccessarily be followed by a statement.
if (forNextMarker.Valid)
{
forNextMarker.MoveToNextStatement();
}
forNextLoopState = new ForNextLoopState(forNextMarker, variableNameToken, startValue, endValue, stepValueToken);
}
else
{
var index = interpreter.CurrentImmediateModeStatementMarker.StatementIndex;
forNextLoopState = new ForNextLoopState(index, variableNameToken, startValue, endValue, stepValueToken);
}
interpreter.ForNextLoops.Push(forNextLoopState);
interpreter.VariablesEnvironment.SetVariableValue(variableNameToken, startValue);
}