private NodeCollection parseStatement()
{
NodeCollection nc;
// statement = "if", expression, statement-list
//if (Grammar.isControl(currentScannerToken))
//{
// StatementList sl;
// GingerToken controlToken = currentScannerToken;
// nextScannerToken();
// Node conditionExpression = parseExpression();
// nextScannerToken();
// if (currentScannerToken == GingerToken.OpenStatementList)
// {
// nextScannerToken();
// sl = parseStatementList(GingerToken.CloseStatementList);
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.OpenStatementList.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// nc = new If(conditionExpression, sl);
//}
// statement = variable
if (Grammar.isType(currentScannerToken))
{
nc = parseVariableDeclaration();
}
// statement = identifier, assignment, expression
else if (currentScannerToken == GingerToken.Identifier)
{
//Identifier identifier = new Identifier(scanner.row, scanner.col, new string(scanner.tokenValue));
Identifier identifier = parseIdentifier(true);
nextScannerToken();
if (currentScannerToken == GingerToken.Assignment)
{
nextScannerToken();
nc = new Assign(identifier, parseExpression());
}
else if (currentScannerToken == GingerToken.OpenPrecedent)
{
ExpressionList exprList = parseExpressionList();
// close-precedent
if (currentScannerToken == GingerToken.ClosePrecedent)
{
nc = new Invocation(identifier, exprList);
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.ClosePrecedent.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Assignment.ToString()} or {GingerToken.OpenPrecedent.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
}
// statement = return [expression]
else if (currentScannerToken == GingerToken.Return)
{
Node expression = null;
spyScannerToken();
if (spiedScannerToken.GetValueOrDefault() != GingerToken.CloseList)
{
nextScannerToken();
expression = parseExpression();
}
nc = new Return(expression);
}
// component = (cont | imp), identifdier, {, function-decs ,}
//else if (Grammar.isComponent(currentScannerToken))
//{
// Component comp;
// Variable componentName;
// GingerToken componentType = currentScannerToken;
// nextScannerToken();
// if (currentScannerToken == GingerToken.Identifier)
// {
// componentName = new Variable(new Identifier(scanner.row, scanner.col, new string(scanner.tokenValue)));
// nextScannerToken();
// if (currentScannerToken == GingerToken.OpenList)
// {
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
//}
// statement = function-declaration = function, type, identifier, open-precedent, variable-list, close-precedent, statement-list
//else if (currentScannerToken == GingerToken.Function)
//{
// if (inFunction)
// {
// throw new ParseException(scanner.row, scanner.col, "Cannot declare function in function", ExceptionLevel.ERROR);
// }
// Variable functionName;
// VarList formalArgsList = new VarList();
// //Type functionReturnType;
// StatementList sl;
// // returns
// //nextScannerToken();
// //if (Grammar.isFunctionType(currentScannerToken))
// //{
// // functionReturnType = parseType();
// //}
// //else
// //{
// // throw new ParseException(scanner.row, scanner.col, $"Expected type, found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// //}
// // identifier
// nextScannerToken();
// if (currentScannerToken == GingerToken.Identifier)
// {
// functionName = new Variable(new Identifier(scanner.row, scanner.col, new string(scanner.tokenValue)));
// // open-precedent
// nextScannerToken();
// if (currentScannerToken == GingerToken.OpenPrecedent)
// {
// // variable-list
// formalArgsList = parseVarList();
// // close-precedent
// if (currentScannerToken == GingerToken.ClosePrecedent)
// {
// nextScannerToken();
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.ClosePrecedent.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// // statement list
// if (currentScannerToken == GingerToken.OpenList)
// {
// nextScannerToken();
// sl = parseStatementList(GingerToken.CloseList, true);
// //nc = new Function(functionName, functionVariableList, functionReturnType, sl);
// nc = new Function(functionName, formalArgsList, sl);
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.OpenList.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.OpenPrecedent.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
//}
else if (currentScannerToken == GingerToken.Sink)
{
nextScannerToken();
if (currentScannerToken == GingerToken.OpenPrecedent)
{
Node expr;
nextScannerToken();
expr = parseExpression();
nextScannerToken();
if (currentScannerToken == GingerToken.ClosePrecedent)
{
if (currentScannerToken == GingerToken.ClosePrecedent)
{
nc = new Sink(parseAnnotation(GingerToken.Low), expr);
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.ClosePrecedent.ToString()} or {GingerToken.Sink.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.ClosePrecedent.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.OpenList.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
}
// statement = component = comp, identifier, as, component-type, statement-list
//else if (currentScannerToken == GingerToken.Component)
//{
// Identifier compName;
// Type compType;
// StatementList sl;
// // identifier
// nextScannerToken();
// if (currentScannerToken == GingerToken.Identifier)
// {
// compName = new Identifier(scanner.row, scanner.col, new string(scanner.tokenValue));
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// // component type
// nextScannerToken();
// if (currentScannerToken == GingerToken.As)
// {
// nextScannerToken();
// if (Grammar.isComponentType(currentScannerToken))
// {
// compType = parseType();
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected component type, found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.As.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
// // statement list
// nextScannerToken();
// if (currentScannerToken == GingerToken.OpenStatementList)
// {
// nextScannerToken();
// sl = parseStatementList(GingerToken.CloseStatementList);
// nc = new Component(compName, compType, sl);
// }
// else
// {
// throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.OpenStatementList.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
// }
//}
else
{
//throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.If.ToString()}', '{GingerToken.Int.ToString()}', or '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
spyScannerToken();
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}' near {spiedScannerToken.ToString()}", ExceptionLevel.ERROR);
}
return(nc);
}
private NodeCollection parseStatement()
{
NodeCollection nc;
// statement = ("if" | "while"), expression, "{", statement-list, "}"
if (Grammar.isControl(currentScannerToken))
{
StatementList sl;
GingerToken controlToken = currentScannerToken;
nextScannerToken();
Node conditionExpression = parseExpression();
nextScannerToken();
if (currentScannerToken == GingerToken.OpenStatementList)
{
nextScannerToken();
sl = parseStatementList(GingerToken.CloseStatementList);
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.OpenStatementList.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
if (controlToken == GingerToken.While)
{
nc = new While(conditionExpression, sl);
}
else
{
nc = new If(conditionExpression, sl);
}
}
// statement = type, identifier
else if (Grammar.isType(currentScannerToken))
{
Node type;
if (currentScannerToken == GingerToken.Int)
{
type = new Integer(scanner.row, scanner.col);
}
else
{
type = new Boolean(scanner.row, scanner.col);
}
nextScannerToken();
if (currentScannerToken != GingerToken.Identifier)
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
else
{
nc = new Declaration(type, new Identifier(scanner.row, scanner.col, new string(scanner.tokenValue)));
}
}
// statement = identifier, "=", expression
else if (currentScannerToken == GingerToken.Identifier)
{
Identifier identifier = new Identifier(scanner.row, scanner.col, new string(scanner.tokenValue));
nextScannerToken();
if (currentScannerToken == GingerToken.Assignment)
{
nextScannerToken();
nc = new Assign(identifier, parseExpression());
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.Assignment.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
}
else
{
throw new ParseException(scanner.row, scanner.col, $"Expected '{GingerToken.If.ToString()}', '{GingerToken.While.ToString()}', '{GingerToken.Int.ToString()}', '{GingerToken.Bool.ToString()}', or '{GingerToken.Identifier.ToString()}', found '{currentScannerToken.ToString()}'", ExceptionLevel.ERROR);
}
return nc;
}