private void GenerateCodeForAssignmentOperator(SplitExpression expression)
{
KeywordToken theOperator = expression.Operator as KeywordToken;
if ((theOperator == null) || (!theOperator.IsModificationOperator))
{
throw new CompilerMessage(ErrorCode.InternalError, "GenerateCodeForAssignmentOperator called without KeywordToken");
}
if (expression.LeftHandSide.Count < 1)
{
throw new CompilerMessage(ErrorCode.OperatorExpectsLeftHandSide, "Expected expression before '" + expression.Operator.Name + "'");
}
if ((theOperator.SymbolType != PredefinedSymbol.PlusPlus) &&
(theOperator.SymbolType != PredefinedSymbol.MinusMinus))
{
GenerateCodeForExpression(expression.RightHandSide);
}
if (theOperator.SymbolType != PredefinedSymbol.SetEqual)
{
GenerateCodeForExpression(expression.LeftHandSide);
}
// TODO: Apply operator
//TODO: GenerateCodeToWriteNewVariableValue
}
private void ProcessKeyword(KeywordToken keywordToken)
{
PredefinedSymbol keyword = keywordToken.SymbolType;
if (keyword == PredefinedSymbol.If)
{
_source.ExpectKeyword(PredefinedSymbol.OpenParenthesis);
Expression condition = ReadExpression(true, PredefinedSymbol.CloseParenthesis);
GenerateCodeForExpression(condition);
ProcessCodeBlock();
if (_source.NextIsKeyword(PredefinedSymbol.Else))
{
ProcessCodeBlock();
}
}
else if (keyword == PredefinedSymbol.While)
{
_source.ExpectKeyword(PredefinedSymbol.OpenParenthesis);
Expression condition = ReadExpression(true, PredefinedSymbol.CloseParenthesis);
GenerateCodeForExpression(condition);
ProcessCodeBlock();
}
else if (keyword == PredefinedSymbol.For)
{
// TODO: Handle for loops
}
else if (keyword == PredefinedSymbol.Break)
{
// TODO: Handle break
}
else if (keyword == PredefinedSymbol.Continue)
{
// TODO: Handle continue
}
else if (keyword == PredefinedSymbol.Return)
{
Expression resultToReturn = ReadExpression(true, PredefinedSymbol.Semicolon);
GenerateCodeForExpression(resultToReturn);
// TODO: Generate code to return and release local vars
FreeAllLocalVariablesButLeaveValid();
}
else
{
throw new CompilerMessage(ErrorCode.InvalidUseOfKeyword, "Keyword '" + keywordToken.Name + "' is not valid here");
}
}
private void ProcessEnumDeclaration()
{
Token enumName = _source.ReadNextTokenAndThrowIfAlreadyDefined();
ScriptEnum enumDefinition = new ScriptEnum(enumName.Name);
enumName.Define(TokenType.EnumType, enumDefinition);
enumName.IsVariableType = true;
_source.ExpectKeyword(PredefinedSymbol.OpenBrace);
int nextEnumValue = 0;
while (!_source.NextIsKeyword(PredefinedSymbol.CloseBrace))
{
Token enumEntry = _source.ReadNextTokenAndThrowIfAlreadyDefined();
KeywordToken nextToken = _source.ReadNextAsKeyword();
if (nextToken.SymbolType == PredefinedSymbol.SetEqual)
{
nextEnumValue = _source.ReadNextAsConstInt();
nextToken = _source.ReadNextAsKeyword();
}
enumDefinition.Values.Add(enumEntry.Name, nextEnumValue);
enumEntry.Define(TokenType.Constant, nextEnumValue);
nextEnumValue++;
if (nextToken.SymbolType == PredefinedSymbol.CloseBrace)
{
break;
}
else if (nextToken.SymbolType != PredefinedSymbol.Comma)
{
throw new CompilerMessage(ErrorCode.UnexpectedToken, "Expected comma at '" + nextToken.Name + "'");
}
}
_source.ExpectKeyword(PredefinedSymbol.Semicolon);
}
private void ProcessKeyword(KeywordToken keywordToken)
{
PredefinedSymbol keyword = keywordToken.SymbolType;
if (keyword == PredefinedSymbol.If)
{
_source.ExpectKeyword(PredefinedSymbol.OpenParenthesis);
Expression condition = ReadExpression(true, PredefinedSymbol.CloseParenthesis);
GenerateCodeForExpression(condition);
ProcessCodeBlock();
if (_source.NextIsKeyword(PredefinedSymbol.Else))
{
ProcessCodeBlock();
}
}
else if (keyword == PredefinedSymbol.While)
{
_source.ExpectKeyword(PredefinedSymbol.OpenParenthesis);
Expression condition = ReadExpression(true, PredefinedSymbol.CloseParenthesis);
GenerateCodeForExpression(condition);
ProcessCodeBlock();
}
else if (keyword == PredefinedSymbol.Return)
{
Expression resultToReturn = ReadExpression(true, PredefinedSymbol.Semicolon);
GenerateCodeForExpression(resultToReturn);
// TODO: Generate code to return and release local vars
FreeAllLocalVariablesButLeaveValid();
}
else
{
throw new CompilerMessage(ErrorCode.InvalidUseOfKeyword, "Keyword '" + keywordToken.Name + "' is not valid here");
}
}