protected override object DoVisit(BinaryExpression binaryExpression)
{
dynamic leftOperand = Visit(binaryExpression.LeftExpression);
dynamic rightOperand = Visit(binaryExpression.RightExpression);
if ((object)leftOperand == Error || (object)rightOperand == Error)
{
return Error;
}
try
{
switch (binaryExpression.Operator.Token)
{
case '=':
return leftOperand == rightOperand;
case '!':
return leftOperand != rightOperand;
case '>':
return leftOperand > rightOperand;
case '<':
return leftOperand < rightOperand;
case ',':
return leftOperand || rightOperand;
case Token.LessOrEqual:
return leftOperand <= rightOperand;
case Token.GreaterOrEqual:
return leftOperand >= rightOperand;
case Token.And:
return leftOperand && rightOperand;
default:
this.errorLogger.LogError(
binaryExpression.Operator.Location,
Utilities.InvariantFormat("Invalid operator \"{0}\".", binaryExpression.Operator.Text));
return Error;
}
}
catch
{
this.errorLogger.LogError(
binaryExpression.Operator.Location,
string.Format(
"Operator \"{0}\" cannot be applied to operands of type \"{1}\" and \"{2}\".",
binaryExpression.Operator.Text,
leftOperand.GetType(),
rightOperand.GetType()));
return Error;
}
}
private Expression ParseCondition(Expression implicitOperand)
{
if (this.nextTokenInfo.Token == Token.Else)
{
this.Consume();
return new ConstantExpression(this.currentTokenInfo.Location, true, "else");
}
Expression condition = null;
do
{
Expression andExpression = null;
do
{
if (this.nextTokenInfo.Token == Token.Else)
{
throw new FormattingException(this.nextTokenInfo.Location, "\"else\" must be used alone.");
}
Operator @operator = this.ParseOperator();
if ([email protected])
{
throw new FormattingException(@operator.Location, "Expected binary operator.");
}
Expression rightOperand = this.ParseUnaryExpression();
var expression = new BinaryExpression(
Location.FromRange(@operator, rightOperand), @operator, implicitOperand, rightOperand);
andExpression = andExpression == null
? expression
: new BinaryExpression(
Location.FromRange(andExpression, expression),
new Operator(Location.Unknown, Token.And, string.Empty),
andExpression,
expression);
}
while (this.nextTokenInfo.Token != ':' && this.nextTokenInfo.Token != ',');
this.Accept(',');
condition = condition == null
? andExpression
: new BinaryExpression(
Location.FromRange(condition, andExpression),
new Operator(this.currentTokenInfo.Location, ','),
condition,
andExpression);
}
while (this.nextTokenInfo.Token != ':');
return condition;
}
