public override Expression VisitBinaryExpression(DreamGrammarParser.BinaryExpressionContext context)
{
return(base.VisitBinaryExpression(context));
}
public override Expression VisitBinaryExpression(DreamGrammarParser.BinaryExpressionContext context)
{
var expressions = new List <Expression>();
foreach (var t in context.children)
{
expressions.Add(t.Accept(this));
}
BinaryExpression binaryExpression = null;
BinaryExpressionTypes currentType = binaryExpressionStack.Peek();
String binaryOperator = RemoveLeadingAndTrailingQuotes(expressions[1].ToString());
switch (binaryOperator)
{
case "+":
case "/":
case "-":
case "*":
case "%":
if (currentType == BinaryExpressionTypes.Int)
{
Expression left;
Expression right;
// Assumptions: Constant Expressions may be wrapped in quotes. So strips quotes.
if (expressions[0] is ConstantExpression)
{
left = Expression.Constant(Convert.ToInt32(RemoveLeadingAndTrailingQuotes(expressions[0].ToString())));
}
else
{
left = expressions[0];
}
if (expressions[2] is ConstantExpression)
{
right = Expression.Constant(Convert.ToInt32(RemoveLeadingAndTrailingQuotes(expressions[2].ToString())));
}
else
{
right = expressions[2];
}
if (binaryOperator.Equals("+"))
{
binaryExpression = Expression.Add(left, right);
}
else if (binaryOperator.Equals("/"))
{
binaryExpression = Expression.Divide(left, right);
}
else if (binaryOperator.Equals("-"))
{
binaryExpression = Expression.Subtract(left, right);
}
else if (binaryOperator.Equals("*"))
{
binaryExpression = Expression.Multiply(left, right);
}
else if (binaryOperator.Equals("%"))
{
binaryExpression = Expression.Modulo(left, right);
}
}
else if (currentType == BinaryExpressionTypes.Double)
{
Expression left;
Expression right;
if (expressions[0] is ConstantExpression)
{
left = Expression.Constant(Convert.ToDouble(RemoveLeadingAndTrailingQuotes(expressions[0].ToString())));
}
else
{
left = expressions[0];
}
if (expressions[2] is ConstantExpression)
{
right = Expression.Constant(Convert.ToDouble(RemoveLeadingAndTrailingQuotes(expressions[2].ToString())));
}
else
{
right = expressions[2];
}
if (binaryOperator.Equals("+"))
{
binaryExpression = Expression.Add(left, right);
}
else if (binaryOperator.Equals("/"))
{
binaryExpression = Expression.Divide(left, right);
}
else if (binaryOperator.Equals("-"))
{
binaryExpression = Expression.Subtract(left, right);
}
else if (binaryOperator.Equals("*"))
{
binaryExpression = Expression.Multiply(left, right);
}
else if (binaryOperator.Equals("%"))
{
binaryExpression = Expression.Modulo(left, right);
}
}
else if (currentType == BinaryExpressionTypes.String)
{
Expression left;
Expression right;
var concatMethod = typeof(string).GetMethod("Concat", new[] { typeof(string), typeof(string) });
if (binaryOperator.Equals("+"))
{
if (expressions[0] is ConstantExpression)
{
left = Expression.Constant(Convert.ToDouble(RemoveLeadingAndTrailingQuotes(expressions[0].ToString())));
}
else
{
left = expressions[0];
}
if (expressions[2] is ConstantExpression)
{
right = Expression.Constant(Convert.ToDouble(RemoveLeadingAndTrailingQuotes(expressions[2].ToString())));
}
else
{
right = expressions[2];
}
binaryExpression = Expression.Add(left, right, concatMethod);
}
}
break;
default:
break;
}
Debug.Assert(binaryExpression != null, "you probably need to add a support for a binary operator");
return(binaryExpression);
}
