/// <summary>
/// Translates the specified expression.
/// </summary>
/// <param name="expression">The expression.</param>
/// <returns></returns>
public virtual Expression Translate(Expression expression)
{
// pre-evaluate local sub-trees
expression = PartialEvaluator.Eval(expression, this.Mapper.Mapping.CanBeEvaluatedLocally);
// apply mapping (binds LINQ operators too)
expression = this.Mapper.Translate(expression);
// any policy specific translations or validations
expression = this.Police.Translate(expression);
// any language specific translations or validations
expression = this.Linguist.Translate(expression);
return(expression);
}
internal IQueryProvider FindProvider(Expression expression, object[] args)
{
Expression root = this.FindProviderInExpression(expression) as ConstantExpression;
if (root == null && args != null && args.Length > 0)
{
Expression replaced = ExpressionReplacer.ReplaceAll(
expression,
this.query.Parameters.ToArray(),
args.Select((a, i) => Expression.Constant(a, this.query.Parameters[i].Type)).ToArray()
);
root = this.FindProviderInExpression(replaced);
}
if (root != null)
{
ConstantExpression cex = root as ConstantExpression;
if (cex == null)
{
cex = PartialEvaluator.Eval(root) as ConstantExpression;
}
if (cex != null)
{
IQueryProvider provider = cex.Value as IQueryProvider;
if (provider == null)
{
IQueryable query = cex.Value as IQueryable;
if (query != null)
{
provider = query.Provider;
}
}
return(provider);
}
}
return(null);
}