public static bool TryTranslate(TranslationContext context, Expression expression, out AstFilter filter)
{
try
{
filter = Translate(context, expression);
return(true);
}
catch (ExpressionNotSupportedException)
{
filter = null;
return(false);
}
}
// caller is responsible for ensuring constant is on the right
public static bool TryTranslateComparisonExpression(TranslationContext context, Expression expression, Expression leftExpression, AstComparisonFilterOperator comparisonOperator, Expression rightExpression, out AstFilter filter)
{
try
{
filter = TranslateComparisonExpression(context, expression, leftExpression, comparisonOperator, rightExpression);
return(true);
}
catch (ExpressionNotSupportedException)
{
filter = null;
return(false);
}
}
public static AstFilter Translate(TranslationContext context, BinaryExpression expression, BinaryExpression moduloExpression, Expression remainderExpression)
{
var fieldExpression = moduloExpression.Left;
var field = ExpressionToFilterFieldTranslator.Translate(context, fieldExpression);
var divisorExpression = moduloExpression.Right;
BsonValue divisor;
BsonValue remainder;
if (divisorExpression.Type == typeof(decimal) && remainderExpression.Type == typeof(decimal))
{
divisor = divisorExpression.GetConstantValue <decimal>(containingExpression: moduloExpression);
remainder = remainderExpression.GetConstantValue <decimal>(containingExpression: expression);
}
else if (divisorExpression.Type == typeof(double) && remainderExpression.Type == typeof(double))
{
divisor = divisorExpression.GetConstantValue <double>(containingExpression: moduloExpression);
remainder = remainderExpression.GetConstantValue <double>(containingExpression: expression);
}
else if (divisorExpression.Type == typeof(float) && remainderExpression.Type == typeof(float))
{
divisor = divisorExpression.GetConstantValue <float>(containingExpression: moduloExpression);
remainder = remainderExpression.GetConstantValue <float>(containingExpression: expression);
}
else if (divisorExpression.Type == typeof(int) && remainderExpression.Type == typeof(int))
{
divisor = divisorExpression.GetConstantValue <int>(containingExpression: moduloExpression);
remainder = remainderExpression.GetConstantValue <int>(containingExpression: expression);
}
else if (divisorExpression.Type == typeof(long) && remainderExpression.Type == typeof(long))
{
divisor = divisorExpression.GetConstantValue <long>(containingExpression: moduloExpression);
remainder = remainderExpression.GetConstantValue <long>(containingExpression: expression);
}
else if (divisorExpression.Type == typeof(uint) && remainderExpression.Type == typeof(uint))
{
divisor = divisorExpression.GetConstantValue <uint>(containingExpression: moduloExpression);
remainder = remainderExpression.GetConstantValue <uint>(containingExpression: expression);
}
else if (divisorExpression.Type == typeof(ulong) && remainderExpression.Type == typeof(ulong))
{
divisor = (long)divisorExpression.GetConstantValue <ulong>(containingExpression: moduloExpression);
remainder = (long)remainderExpression.GetConstantValue <ulong>(containingExpression: expression);
}
else
{
throw new ExpressionNotSupportedException(expression);
}
var moduloComparisonAst = AstFilter.Mod(field, divisor, remainder);
switch (expression.NodeType)
{
case ExpressionType.Equal:
return(moduloComparisonAst);
case ExpressionType.NotEqual:
return(AstFilter.Not(moduloComparisonAst));
}
throw new ExpressionNotSupportedException(expression);
}
