private ExpressionSyntax ParseSubExpression(ExpressionSyntax left, int precedence)
{
if (left == null)
{
// No left operand, so we parse one and take care of leading unary operators
var unaryExpression = SyntaxFacts.GetUnaryOperatorExpression(Current.Kind);
left = unaryExpression == SyntaxKind.BadToken
? ParseSimpleExpression()
: ParseUnaryExpression(unaryExpression);
}
while (Current.Kind != SyntaxKind.EndOfFileToken)
{
// Special handling for NOT BETWEEN, NOT IN, NOT LIKE, NOT SIMILAR TO, and NOT SOUND SLIKE.
var notKeyword = Current.Kind == SyntaxKind.NotKeyword && Lookahead.Kind.CanHaveLeadingNot()
? NextToken()
: null;
// Special handling for the only ternary operator BETWEEN
if (Current.Kind == SyntaxKind.BetweenKeyword)
{
var operatorPrecedence = SyntaxFacts.GetTernaryOperatorPrecedence(SyntaxKind.BetweenExpression);
if (operatorPrecedence <= precedence)
{
return(left);
}
left = ParseBetweenExpression(left, notKeyword);
}
else
{
// If there is no binary operator we are finished
var binaryExpression = SyntaxFacts.GetBinaryOperatorExpression(Current.Kind);
if (binaryExpression == SyntaxKind.BadToken)
{
return(left);
}
var operatorPrecedence = SyntaxFacts.GetBinaryOperatorPrecedence(binaryExpression);
// Precedence is lower or equal, parse it later
if (operatorPrecedence <= precedence)
{
return(left);
}
// Precedence is higher
left = ParseBinaryExpression(left, notKeyword, binaryExpression, operatorPrecedence);
}
}
return(left);
}
