/// <summary>
/// Parses a for command
/// </summary>
private ICommandNode ParseForCommand()
{
Debugger.Write("Parsing For Command");
Position startPosition = CurrentToken.Position;
Accept(TokenType.For);
IdentifierNode identifier = ParseIdentifier();
// Declare I as a new variable of type integer with an undefined value
VarDeclarationNode declaration = new VarDeclarationNode(identifier,
new TypeDenoterNode(
new IdentifierNode(
new Token(TokenType.Identifier, "Integer", startPosition))), startPosition);
// Evaluate E1
Accept(TokenType.Becomes);
IExpressionNode becomesExpression = ParseExpression();
// Assign I to the value of E1
AssignCommandNode assign = new AssignCommandNode(identifier, becomesExpression);
// Evaluate E2
Accept(TokenType.To);
IExpressionNode toExpression = ParseExpression();
Accept(TokenType.Do);
// Execute command
ICommandNode command = ParseSingleCommand();
Accept(TokenType.Next);
return(new ForCommandNode(declaration, assign, toExpression, command, startPosition));
}
/// <summary>
/// Carries out type checking on an assign command node
/// </summary>
/// <param name="assignCommand">The node to perform type checking on</param>
private void PerformTypeCheckingOnAssignCommand(AssignCommandNode assignCommand)
{
PerformTypeChecking(assignCommand.Identifier);
PerformTypeChecking(assignCommand.Expression);
if (!(assignCommand.Identifier.Declaration is IVariableDeclarationNode varDeclaration))
{
Reporter.ReportError("identifier is not a variable");
}
/// <summary>
/// Carries out type checking on an assign command node
/// </summary>
/// <param name="assignCommand">The node to perform type checking on</param>
private void PerformTypeCheckingOnAssignCommand(AssignCommandNode assignCommand)
{
PerformTypeChecking(assignCommand.Identifier);
PerformTypeChecking(assignCommand.Expression);
if (!(assignCommand.Identifier.Declaration is IVariableDeclarationNode typeDenoterDeclaration))
{
// Error - identifier is not a variable
AddToErrorPositions(assignCommand.Position, "Identifier is not a variable");
}
/// <summary>
/// Carries out type checking on an assign command node
/// </summary>
/// <param name="assignCommand">The node to perform type checking on</param>
private void PerformTypeCheckingOnAssignCommand(AssignCommandNode assignCommand)
{
PerformTypeChecking(assignCommand.Identifier);
PerformTypeChecking(assignCommand.Expression);
if (!(assignCommand.Identifier.Declaration is IVariableDeclarationNode varDeclaration))
{
// Error - identifier is not a variable
Debugger.WriteDebuggingInfo("Error on Assign command is not a variable");
}
/// <summary>
/// Carries out type checking on an assign command node
/// </summary>
/// <param name="assignCommand">The node to perform type checking on</param>
private void PerformTypeCheckingOnAssignCommand(AssignCommandNode assignCommand)
{
PerformTypeChecking(assignCommand.Identifier);
PerformTypeChecking(assignCommand.Expression);
// Check identifier is a variable
if (!(assignCommand.Identifier.Declaration is IVariableDeclarationNode varDeclaration))
{
Debugger.Write("Error: identifier is not a variable");
}
/// <summary>
/// Generates code for an assign command node
/// </summary>
/// <param name="assignCommand">The node to generate code for</param>
private void GenerateCodeForAssignCommand(AssignCommandNode assignCommand)
{
Debugger.Write("Generating code for Assign Command");
GenerateCodeFor(assignCommand.Expression);
if (assignCommand.Identifier.Declaration is IVariableDeclarationNode varDeclaration)
{
code.AddInstruction(varDeclaration.RuntimeEntity.GenerateInstructionToStore());
}
else
{
Debugger.Write("The identifier is not a variable and you should have picked this problem up during type checking");
}
}
/// <summary>
/// Carries out type checking on an assign command node
/// </summary>
/// <param name="assignCommand">The node to perform type checking on</param>
private void PerformTypeCheckingOnAssignCommand(AssignCommandNode assignCommand)
{
PerformTypeChecking(assignCommand.Identifier);
PerformTypeChecking(assignCommand.Expression);
if (!(assignCommand.Identifier.Declaration is IVariableDeclarationNode varDeclaration))
{
// Error - identifier is not a variable
Debugger.Write("Error on Assign command is not a variable");
//Reporter.ReportError($"Error on Assign command is not a variable {assignCommand.Position.ToString()}");
}
public ICommandNode ParseFor()
{
Debugger.Write("Parsing for command");
Position startPosition = CurrentToken.Position;
Accept(For);
AssignCommandNode assign = AssignForCommand();
Accept(To);
IExpressionNode expression = ParseExpression();
Accept(Do);
ICommandNode command = ParseSingleCommand();
Accept(Next);
return(new ForCommandNode(assign, expression, command, startPosition));
}
/// <summary>
/// Carries out identification on an assign command node
/// </summary>
/// <param name="assignCommand">The node to perform identification on</param>
private void PerformIdentificationOnAssignCommand(AssignCommandNode assignCommand)
{
PerformIdentification(assignCommand.Identifier);
PerformIdentification(assignCommand.Expression);
}
