public override void Execute(Interpreter interpreter, TokenMarker tokenMarker)
{
var variableNameToken = tokenMarker.Token as VariableNameToken;
ValueTokenArray indicies = null;
if (variableNameToken == null)
{
throw new Exceptions.SyntaxErrorException();
}
if (tokenMarker.PeekNext() is OpenParenToken)
{
indicies = interpreter.ExpressionEvaluator.EvaluateVariableArrayAssignment(tokenMarker);
}
else
{
tokenMarker.MoveNext();
}
var equalsToken = tokenMarker.Token;
if (!(equalsToken is Operators.EqualToken))
{
throw new Exceptions.SyntaxErrorException();
}
if (tokenMarker.GetNextToken() == null)
{
throw new Exceptions.SyntaxErrorException();
}
var result = interpreter.ExpressionEvaluator.Evaluate(tokenMarker);
interpreter.VariablesEnvironment.SetVariableValue(variableNameToken, indicies, result);
}
public override void Execute(Interpreter interpreter, TokenMarker tokenMarker)
{
while (tokenMarker.Token != null)
{
if (!(tokenMarker.Token is VariableNameToken variableNameToken))
{
throw new Exceptions.SyntaxErrorException();
}
if (!(tokenMarker.PeekNext() is OpenParenToken))
{
throw new Exceptions.SyntaxErrorException();
}
var indicies = interpreter.ExpressionEvaluator.EvaluateVariableArrayAssignment(tokenMarker);
interpreter.VariablesEnvironment.DimensionArrayVariable(variableNameToken, indicies);
if (!(tokenMarker.Token is CommaToken))
{
break;
}
tokenMarker.MoveNext();
}
}
public override void Execute(Interpreter interpreter, TokenMarker tokenMarker)
{
if (tokenMarker.Token == null)
{
interpreter.Run();
return;
}
if (!(tokenMarker.Token is NumericValueToken numericValueToken))
{
throw new Exceptions.SyntaxErrorException();
}
if (tokenMarker.PeekNext() != null)
{
throw new Exceptions.SyntaxErrorException();
}
interpreter.Run(numericValueToken.IntValue);
}
public override void Execute(Interpreter interpreter, TokenMarker tokenMarker)
{
while (tokenMarker.Token != null)
{
ValueTokenArray indicies = null;
if (!(tokenMarker.Token is VariableNameToken variableNameToken))
{
throw new Exceptions.SyntaxErrorException();
}
if (tokenMarker.PeekNext() is OpenParenToken)
{
indicies = interpreter.ExpressionEvaluator.EvaluateVariableArrayAssignment(tokenMarker);
}
else
{
tokenMarker.MoveNext();
}
var valueToken = interpreter.ReadNextDataValue();
if (valueToken == null)
{
throw new Exceptions.OutOfDataException();
}
switch (variableNameToken.VariableType)
{
case VariableValueType.String:
break;
case VariableValueType.RealNumber:
float realValue = 0;
var success = float.TryParse(((StringValueToken)valueToken).Value, out realValue);
if (success == false)
{
throw new Exceptions.TypeMismatchException();
}
valueToken = interpreter.TokensProvider.CreateRealValueToken(realValue);
break;
case VariableValueType.IntegerNumber:
success = float.TryParse(((StringValueToken)valueToken).Value, out realValue);
if (success == false)
{
throw new Exceptions.TypeMismatchException();
}
// In Commodore BASIC, a READ of a number with a decimal into an integer number produces a zero.
int intValue = (int)Math.Abs(realValue);
if (realValue != intValue)
{
intValue = 0;
}
if (intValue < Int16.MinValue || intValue > Int16.MaxValue)
{
throw new Exceptions.OverflowException();
}
valueToken = interpreter.TokensProvider.CreateIntegerValueToken((Int16)intValue);
break;
}
interpreter.VariablesEnvironment.SetVariableValue(variableNameToken, indicies, valueToken);
if (tokenMarker.Token == null)
{
break;
}
if (!(tokenMarker.Token is CommaToken))
{
throw new Exceptions.SyntaxErrorException();
}
tokenMarker.MoveNext();
// The next token should now be a variable name token
}
}
public override void Execute(Interpreter interpreter, TokenMarker tokenMarker)
{
if (interpreter.InterpreterMode == InterpreterMode.Immmediate)
{
throw new Exceptions.IllegalDirectModeException();
}
var variableNameTokens = new List <(VariableNameToken, ValueTokenArray)>();
while (tokenMarker.Token != null)
{
ValueTokenArray indicies = null;
if (!(tokenMarker.Token is VariableNameToken variableNameToken))
{
throw new Exceptions.SyntaxErrorException();
}
if (tokenMarker.PeekNext() is OpenParenToken)
{
indicies = interpreter.ExpressionEvaluator.EvaluateVariableArrayAssignment(tokenMarker);
}
else
{
tokenMarker.MoveNext();
}
if (tokenMarker.Token != null && !(tokenMarker.Token is CommaToken))
{
throw new Exceptions.SyntaxErrorException();
}
variableNameTokens.Add((variableNameToken, indicies));
}
foreach (var(nameToken, indicies) in variableNameTokens)
{
var input = interpreter.Console.ReadChar();
switch (nameToken.VariableType)
{
case VariableValueType.String:
string inputString = (input != null) ? input.ToString() : string.Empty;
interpreter.VariablesEnvironment.SetVariableValue(nameToken, indicies,
interpreter.TokensProvider.CreateStringValueToken(inputString));
break;
case VariableValueType.RealNumber:
float realValue;
if (input == null)
{
realValue = 0;
}
else
{
if (input >= '0' && input <= '9')
{
realValue = (float)(input - '0');
}
else
{
throw new Exceptions.SyntaxErrorException();
}
}
interpreter.VariablesEnvironment.SetVariableValue(nameToken, indicies,
interpreter.TokensProvider.CreateRealValueToken(realValue));
break;
case VariableValueType.IntegerNumber:
Int16 intValue;
if (input == null)
{
intValue = 0;
}
else
{
if (input >= '0' && input <= '9')
{
intValue = (Int16)(input - '0');
}
else
{
throw new Exceptions.SyntaxErrorException();
}
}
interpreter.VariablesEnvironment.SetVariableValue(nameToken, indicies,
interpreter.TokensProvider.CreateIntegerValueToken(intValue));
break;
}
if (input == null)
{
Thread.Sleep(100);
}
}
}
public override void Execute(Interpreter interpreter, TokenMarker tokenMarker)
{
var firstToken = tokenMarker.Token;
if (firstToken == null)
{
throw new Exceptions.SyntaxErrorException();
}
// Is there an input prompt?
if (firstToken is StringValueToken stringValueToken)
{
interpreter.Console.OutputTextWriter.Write(stringValueToken.Value);
interpreter.Console.OutputTextWriter.Write("? ");
tokenMarker.MoveNext();
// Ensure a semicolon follows the input prompt.
if ((tokenMarker.Token == null) || !(tokenMarker.Token is SemicolonToken))
{
throw new Exceptions.SyntaxErrorException();
}
tokenMarker.MoveNext();
}
else
{
interpreter.Console.OutputTextWriter.Write("? ");
}
// Now make a list of the variable names the input will be parsed into.
var variableNameTokens = new List <(VariableNameToken, ValueTokenArray)>();
while (tokenMarker.Token != null)
{
if (!(tokenMarker.Token is VariableNameToken variableNameToken))
{
throw new Exceptions.SyntaxErrorException();
}
ValueTokenArray indicies = null;
// For an array variable, get the array indicies.
if (tokenMarker.PeekNext() is OpenParenToken)
{
indicies = interpreter.ExpressionEvaluator.EvaluateVariableArrayAssignment(tokenMarker);
}
else
{
tokenMarker.MoveNext();
}
variableNameTokens.Add((variableNameToken, indicies));
if (tokenMarker.Token == null)
{
break;
}
// Make sure a comma is the next token
if (!(tokenMarker.Token is CommaToken))
{
throw new Exceptions.SyntaxErrorException();
}
tokenMarker.MoveNext();
}
if (variableNameTokens.Count == 0)
{
throw new Exceptions.SyntaxErrorException();
}
// Add default value for inputs
var tokenResults = new List <ValueToken>();
foreach (var(variableNameToken, indicies) in variableNameTokens)
{
switch (variableNameToken.VariableType)
{
case VariableValueType.String:
tokenResults.Add(interpreter.TokensProvider.CreateStringValueToken(string.Empty));
break;
case VariableValueType.RealNumber:
tokenResults.Add(interpreter.TokensProvider.CreateRealValueToken(0));
break;
case VariableValueType.IntegerNumber:
tokenResults.Add(interpreter.TokensProvider.CreateIntegerValueToken(0));
break;
}
}
int tokenResultsIndex = 0;
// Get input. Support the quirks of Microsoft's 6502 BASIC I could discover.
bool getMoreInput = true;
while (getMoreInput)
{
string inputLine = interpreter.Console.ReadLine()?.ToUpper();
if (inputLine == null)
{
// Probably received a Ctrl-C.
interpreter.BreakDetected();
return;
}
/* A quirk of Microsoft BASIC's INPUT implementation is that pressing return without entering anything
* uses the default or what has been previously input. */
if (inputLine.Length == 0)
{
getMoreInput = false;
break;
}
int index = 0;
bool parseSuccess = true;
while (index < inputLine.Length && parseSuccess && tokenResultsIndex < tokenResults.Count)
{
parseSuccess = ParseNextInput(inputLine, index, out index, out string parsedInput, out ParseFailureReason parseFailureReason);
// Still assign the input to a variable even if the parse failed. Another Microsoft BASIC quirk.
bool assignmentSuccess = AssignInputToVariable(interpreter,
variableNameTokens[tokenResultsIndex].Item1,
variableNameTokens[tokenResultsIndex].Item2,
parsedInput);
if (!parseSuccess)
{
switch (parseFailureReason)
{
// Because characters followed a closing quote but shouldn't, write out a redo from start message and start over.
case ParseFailureReason.CharactersAfterQuote:
// Set to -1 since one will be added below to bring the index back to zero
tokenResultsIndex = -1;
interpreter.Console.OutputTextWriter.WriteLine($"{ErrorMessages.errorStart} {ErrorMessages.redoFromStart}");
break;
// No error output for a colon, except when it involves the last result.
case ParseFailureReason.Colon:
if (tokenResultsIndex + 1 == tokenResults.Count)
{
interpreter.Console.OutputTextWriter.WriteLine($"{ErrorMessages.errorStart} {ErrorMessages.extraIgnored}");
}
break;
}
}
tokenResultsIndex += 1;
}
if (tokenResultsIndex < tokenResults.Count)
{
// Still need more input and no more input is on this line. Ask for more.
if (index >= inputLine.Length)
{
interpreter.Console.OutputTextWriter.Write("?? ");
continue;
}
}
else
{
// For too much input, write out an extra ignored message.
if (index < inputLine.Length)
{
interpreter.Console.OutputTextWriter.WriteLine($"{ErrorMessages.errorStart} {ErrorMessages.extraIgnored}");
}
getMoreInput = false;
}
}
}