private void ParseExpressionSegment()
{
#region Chart
// arraycre new : type : [{
// literal (lit)
// simpleName ident
// parenExpr LParen : expr
// memAccess pexpr : Dot
// pdefType : Dot
// invoke pexpr : LParen
// elemAccess noArrCreExpr: LBracket
// thisAccess this
// baseAccess base : Dot
// base : LBracket
// postInc pexpr : ++
// postDec pexpr : --
// objCre new : type : LParen
// delgCre new : delgType : LParen
// typeof typeof : LParen
// checked checked : LParen
// unchecked unchecked : LParen
#endregion
ExpressionNode tempNode = null;
TokenID startToken = curtok.ID;
switch (curtok.ID)
{
#region Literals
case TokenID.NullLiteral:
exprStack.Push(new NullPrimitive(curtok));
Advance();
break;
case TokenID.TrueLiteral:
exprStack.Push(new BooleanPrimitive(true, curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.FalseLiteral:
exprStack.Push(new BooleanPrimitive(false, curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.IntLiteral:
exprStack.Push(new IntegralPrimitive(strings[curtok.Data], IntegralType.Int, curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.UIntLiteral:
exprStack.Push(new IntegralPrimitive(strings[curtok.Data], IntegralType.UInt, curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.LongLiteral:
exprStack.Push(new IntegralPrimitive(strings[curtok.Data], IntegralType.Long, curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.ULongLiteral:
exprStack.Push(new IntegralPrimitive(strings[curtok.Data], IntegralType.ULong, curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.RealLiteral:
exprStack.Push(new RealPrimitive(strings[curtok.Data], curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.CharLiteral:
exprStack.Push(new CharPrimitive(strings[curtok.Data], curtok));
Advance();
ParseContinuingPrimary();
break;
case TokenID.StringLiteral:
string sval = strings[curtok.Data];
exprStack.Push(new StringPrimitive(sval, curtok));
Advance();
ParseContinuingPrimary();
break;
#endregion
#region Predefined Types
case TokenID.Bool:
case TokenID.Byte:
case TokenID.Char:
case TokenID.Decimal:
case TokenID.Double:
case TokenID.Float:
case TokenID.Int:
case TokenID.Long:
case TokenID.Object:
case TokenID.SByte:
case TokenID.Short:
case TokenID.String:
case TokenID.UInt:
case TokenID.ULong:
case TokenID.UShort:
exprStack.Push(ParseIdentifierOrKeyword(false, true, false, false));
if (curtok.ID == TokenID.Question)
{
Advance();
((INullableType)exprStack.Peek()).IsNullableType = true;
}
else
{
if (curtok.ID == TokenID.Star)
{
Advance();
exprStack.Push(new TypePointerNode(exprStack.Pop()));
}
}
ParseContinuingPrimary();
break;
#endregion
#region Binary Ops
case TokenID.Plus:
tempNode = ConsumeBinary(startToken);
if (tempNode != null)
{
exprStack.Push(new UnaryExpression(startToken, tempNode, tempNode.RelatedToken)); // unary
}
break;
case TokenID.Minus:
if (exprStack.Count != 0 && exprStack.Peek() is PrimaryExpression)
{
tempNode = ConsumeBinary(startToken);
}
else
{
ConsumeUnary(TokenID.Minus);
}
if (tempNode != null)
{
exprStack.Push(new UnaryExpression(startToken, tempNode, tempNode.RelatedToken)); // unary
}
break;
case TokenID.Star:
// for this token, we have to control it is not a
// pointer type declaration
bool isPointer = false;
if ( exprStack.Count == 0
|| !(exprStack.Peek() is IPointer) &&
(curTokNode != null && curTokNode.Value.ID == TokenID.Star || curTokNode.Previous.Previous.Value.ID == TokenID.Star))
{
// case :
// int* p;
// *p = x;
Advance();//over the '*';
ParseExpressionSegment();
exprStack.Push(new DereferenceExpression(exprStack.Pop(), true ));
}
else
{
if (isLocalConst // if const kw -> local/member declaration
|| exprStack.Peek() is IPointer)
{
//the expression inherits from IPointer, so this is a type expression
//and it might be a pointer
isPointer = true;
}
else
{
// if the next segment can not be an expression
TokenID id = (curTokNode != null) ? curTokNode.Value.ID : TokenID.Eof;
if (id == TokenID.Eof || id == TokenID.RCurly ||
id == TokenID.Semi || id == TokenID.RParen ||
id == TokenID.Comma || id == TokenID.Colon)
{
isPointer = true;
}
}
if (isPointer)
{
Advance();
ExpressionNode e = TagAsPointerType(exprStack.Pop());
exprStack.Push(e);
}
else
{
//the next segment is an expression.
//at this sage it is impossible to determine if this is a pointer expression
ConsumeBinary(startToken);
if (curtok.ID == TokenID.Equal)
{
// the assignment means that the previous expression is not
// a binary expression but a local pointer declaration
Advance(); // over equal
BinaryExpression bin = (BinaryExpression)exprStack.Pop();
LocalDeclarationStatement ldecl = new LocalDeclarationStatement((IType)TagAsPointerType(bin.Left), (IdentifierExpression)bin.Right, ParseExpression(TokenID.Comma) );
exprStack.Push(ldecl);
if (curtok.ID == TokenID.Comma)// multiple local declaration
{
exprStack.Push((ExpressionNode)ldecl.Type);
ParseLocalDeclaration();
}
}
}
}
break;
case TokenID.Is:
case TokenID.As:
case TokenID.Slash:
case TokenID.Percent:
case TokenID.ShiftLeft:
case TokenID.ShiftRight:
case TokenID.Less:
case TokenID.Greater:
case TokenID.LessEqual:
case TokenID.GreaterEqual:
case TokenID.EqualEqual:
case TokenID.NotEqual:
case TokenID.BXor:
case TokenID.BOr:
case TokenID.And:
case TokenID.Or:
ConsumeBinary(startToken);
break;
case TokenID.BAnd:
if (exprStack.Count == 0)
{
//the expression stack is empty, so this is n identifier dereference
ParseAddressOfIdentifier();
}
else
{
ConsumeBinary(startToken);
}
break;
#endregion
#region Unary Ops
case TokenID.Not:
case TokenID.Tilde:
case TokenID.PlusPlus:
case TokenID.MinusMinus:
ConsumeUnary(startToken);
break;
#endregion
#region Conditional
case TokenID.Question:
if (curtok.NullableDeclaration)
{
Advance();
ExpressionNode expr = TagAsNullableType(exprStack.Pop());
CheckRankSpecifier(expr);
exprStack.Push(expr);
}
else
{
Advance();
ConditionalExpression conditionalExpression = new ConditionalExpression(exprStack.Pop(), null, null);
exprStack.Push(conditionalExpression);
ExpressionNode cond1 = ParseExpression(TokenID.Equal);
AssertAndAdvance(TokenID.Colon);
ExpressionNode cond2 = ParseExpression();
conditionalExpression.Left = cond1;
conditionalExpression.Right = cond2;
}
break;
//case TokenID.ColonColon:
// Advance();
//break;
case TokenID.QuestionQuestion:
ExpressionNode left = exprStack.Pop();
Advance();
ExpressionNode right = ParseExpression(TokenID.Semi);
exprStack.Push(new NullCoalescingExpression(left, right ));
break;
#endregion
#region Keywords
// keywords
case TokenID.Ref:
Advance();
ParseExpressionSegment();
exprStack.Push(new RefNode(exprStack.Pop()));
break;
case TokenID.Out:
Advance();
ParseExpressionSegment();
exprStack.Push(new OutNode(exprStack.Pop()));
break;
case TokenID.This:
exprStack.Push(ParseIdentifierOrKeyword(false, true, false, false));
ParseContinuingPrimary();
break;
case TokenID.Void:
// this can happen in typeof(void), nothing can follow
exprStack.Push(new VoidPrimitive(curtok));
Advance();
break;
case TokenID.Base:
Advance();
TokenID newToken = curtok.ID;
if (newToken == TokenID.Dot)
{
Advance();// advance over dot
exprStack.Push( new IdentifierExpression(strings[curtok.Data], curtok) );
Advance();//advance over ident
}
else if (newToken == TokenID.LBracket)
{
Advance();//advance over left bracket
exprStack.Push( ParseExpressionList(TokenID.RBracket) );
}
ParseContinuingPrimary();
exprStack.Push(new BaseAccessExpression(exprStack.Pop()));
break;
case TokenID.Typeof:
Advance();
AssertAndAdvance(TokenID.LParen);
exprStack.Push(new TypeOfExpression(ParseExpression(TokenID.RParen)));
AssertAndAdvance(TokenID.RParen);
ParseContinuingPrimary();
break;
case TokenID.Checked:
Advance();
AssertAndAdvance(TokenID.LParen);
//ParseExpressionSegment();
exprStack.Push(new CheckedExpression(ParseExpression(TokenID.RParen)));
AssertAndAdvance(TokenID.RParen);
ParseContinuingPrimary();
break;
case TokenID.Unchecked:
Advance();
AssertAndAdvance(TokenID.LParen);
ParseExpressionSegment();
exprStack.Push(new UncheckedExpression(exprStack.Pop()));
AssertAndAdvance(TokenID.RParen);
ParseContinuingPrimary();
break;
#endregion
#region Assignment
case TokenID.Equal:
case TokenID.PlusEqual:
case TokenID.MinusEqual:
case TokenID.StarEqual:
case TokenID.SlashEqual:
case TokenID.PercentEqual:
case TokenID.BAndEqual:
case TokenID.BOrEqual:
case TokenID.BXorEqual:
case TokenID.ShiftLeftEqual:
case TokenID.ShiftRightEqual:
TokenID op = curtok.ID;
Advance();
if (exprStack.Count > 0 && !(exprStack.Peek() is PrimaryExpression) && !(exprStack.Peek() is UnaryCastExpression))
{
ReportError("Left hand side of assignment must be a variable.");
}
ExpressionNode assignVar = exprStack.Pop();
ExpressionNode rightSide = ParseExpression();
exprStack.Push(new AssignmentExpression(op, assignVar, rightSide));
break;
#endregion
#region Generic
case TokenID.Default:
Advance();
AssertAndAdvance(TokenID.LParen);
ParseTypeParameterNode(false, false, false);
AssertAndAdvance(TokenID.RParen);
exprStack.Push(new DefaultConstantExpression(curTypeParameters[0] ));
curTypeParameters = new List<TypeParameterNode>();
ParseContinuingPrimary();
break;
#endregion
case TokenID.LCurly:
ArrayInitializerExpression aie = new ArrayInitializerExpression(curtok);
Advance();
exprStack.Push(aie);
aie.Expressions = ParseExpressionList(TokenID.RCurly);
break;
case TokenID.New:
Advance();
isNewStatement = true;
// TODO : new int*() is allowed ?
IType newType = ParseType();
//ApplyTypeParameters(newType); -> not sure, but a type pointer can not be generic!
if (curtok.ID == TokenID.LParen)
{
Advance();
ExpressionList newList = ParseExpressionList(TokenID.RParen);
exprStack.Push(new ObjectCreationExpression(newType, newList, newList.RelatedToken));
}
else if (curtok.ID == TokenID.LBracket)
{
ParseArrayCreation(newType);
}
ParseContinuingPrimary();
isNewStatement = false;
break;
case TokenID.Ident:
//test for local decl
bool isDecl = isAfterType();
if (isDecl)
{
ParseLocalDeclaration();
}
else
{
ExpressionNode expr = ParseIdentifierOrKeyword(false, true, false, false);
exprStack.Push(expr);
ParseContinuingPrimary();
}
break;
case TokenID.LParen:
Advance();
ParseCastOrGroup();
break;
case TokenID.Delegate://anonymous method
Advance();
ParseAnonymousMethod();
break;
case TokenID.Sizeof:
ParseSizeOf();
break;
case TokenID.Stackalloc:
ParseStackalloc();
break;
case TokenID.MinusGreater:
// pointer member access
ParseContinuingPrimary();
break;
default:
if (Lexer.IsKeyWord(curtok.ID))
{
// in this case a key word is used like a variable name.
goto case TokenID.Ident;
}
else
{
RecoverFromError("Unhandled case in ParseExpressionSegment ", curtok.ID); // todo: fill out error report
}
break;
}
}
private ExpressionNode ParseSubexpression(int precBound, ExpressionNode left)
{
while (true)
{
int curPrec = precedence[(int)curtok.ID];
if (curPrec < precBound) break;
int associativity = ASSOC_LEFT;
TokenID curOp = curtok.ID;
switch (curOp)
{
case TokenID.Equal:
case TokenID.PlusEqual:
case TokenID.MinusEqual:
case TokenID.StarEqual:
case TokenID.SlashEqual:
case TokenID.PercentEqual:
case TokenID.BAndEqual:
case TokenID.BOrEqual:
case TokenID.BXorEqual:
case TokenID.ShiftLeftEqual:
case TokenID.QuestionQuestion:
associativity = ASSOC_RIGHT;
goto case TokenID.Percent; // "FALL THROUGH"
case TokenID.Greater:
Advance();
if (curtok.ID == TokenID.Greater && curtok.LastCharWasGreater)
{
curOp = TokenID.ShiftRight;
Advance();
}
else if (curtok.ID == TokenID.GreaterEqual && curtok.LastCharWasGreater)
{
curOp = TokenID.ShiftRightEqual;
associativity = ASSOC_RIGHT;
Advance();
}
goto parseBinOp;
case TokenID.Or:
case TokenID.And:
case TokenID.BOr:
case TokenID.BXor:
case TokenID.BAnd:
case TokenID.EqualEqual:
case TokenID.NotEqual:
case TokenID.Less:
case TokenID.LessEqual:
case TokenID.GreaterEqual:
case TokenID.ShiftLeft:
case TokenID.Plus:
case TokenID.Minus:
case TokenID.Star:
case TokenID.Slash:
case TokenID.Percent:
Advance();
parseBinOp: left = new BinaryExpression(curOp, left, ParseSubexpression(curPrec + associativity));
break;
case TokenID.PlusPlus: // postfix
Advance();
left = new PostIncrementExpression(left);
break;
case TokenID.MinusMinus: // postfix
Advance();
left = new PostDecrementExpression(left);
break;
case TokenID.Is:
case TokenID.As:
Advance();
left = new BinaryExpression(curOp, left, ParseType(true));
break;
case TokenID.Question:
{
Advance();
ExpressionNode thenExpr = ParseExpression();
AssertAndAdvance(TokenID.Colon);
left = new ConditionalExpression(left, thenExpr, ParseExpression());
break;
}
case TokenID.LParen: // invocation
Advance();
left = new InvocationExpression(left, ParseArgumentList());
AssertAndAdvance(TokenID.RParen);
break;
case TokenID.LBracket: // element access
Advance();
left = new ElementAccessExpression(left, ParseExpressionList());
AssertAndAdvance(TokenID.RBracket);
break;
case TokenID.Dot: // member access
case TokenID.MinusGreater:
left = ParseMemberAccess(left);
break;
default:
ReportError("Unexpected token", curtok);
return left;
}
}
return left;
}
private void ParseExpressionSegment()
{
#region Chart
// baseAccess base : Dot
// base : LBracket
// delgCre new : delgType : LParen
// typeof typeof : LParen
// checked checked : LParen
// unchecked unchecked : LParen
#endregion
bool stackCountUnaltered = false;
int startStackCount = exprStack.Count;
TokenID startToken = curtok.ID;
switch (curtok.ID)
{
#region Conditional
case TokenID.Question:
mayBeLocalDecl = false;
stackCountUnaltered = true;
if (curtok.NullableDeclaration)
{
Advance();
ExpressionNode expr = TagAsNullableType(exprStack.Pop());
CheckRankSpecifier(expr);
exprStack.Push(expr);
}
else
{
Advance();
ConditionalExpression conditionalExpression = new ConditionalExpression(exprStack.Pop(), null, null);
exprStack.Push(conditionalExpression);
ExpressionNode cond1 = ParseExpression(TokenID.Equal);
AssertAndAdvance(TokenID.Colon);
ExpressionNode cond2 = ParseExpression();
conditionalExpression.Left = cond1;
conditionalExpression.Right = cond2;
}
break;
#endregion
#region Keywords
// keywords
case TokenID.Ref:
mayBeLocalDecl = false;
Advance();
ParseExpressionSegment();
exprStack.Push(new RefNode(exprStack.Pop()));
break;
case TokenID.Out:
mayBeLocalDecl = false;
Advance();
ParseExpressionSegment();
exprStack.Push(new OutNode(exprStack.Pop()));
break;
case TokenID.Void:
// this can happen in typeof(void) or void* x;
exprStack.Push(new VoidPrimitive(curtok));
Advance();
if (curtok.ID == TokenID.Star)
{
do
{
Advance();
exprStack.Push(new TypePointerNode(exprStack.Pop()));
}
while (curtok.ID == TokenID.Star);
}
else
mayBeLocalDecl = false;
break;
#endregion
case TokenID.Stackalloc:
mayBeLocalDecl = false;
ParseStackalloc();
break;
}
if (exprStack.Count != startStackCount + (stackCountUnaltered ? 0 : 1))
{
ReportError("Internal compiler error: Expression stack inconsistent!", curtok);
}
}
public virtual object VisitConditionalExpression(ConditionalExpression conditionalExpression, object data)
{
stackMap.Push(conditionalExpression);
conditionalExpression.Test.AcceptVisitor(this, data);
conditionalExpression.Left.AcceptVisitor(this, data);
conditionalExpression.Right.AcceptVisitor(this, data);
stackMap.Pop();
return null;
}
