/// <summary>
/// We have to protect the lambda expression's parameters from accidental translation.
///
/// If a parameter is called "t" to a lambda function, and the parameter is defined above us in some other
/// context, then we need to make sure that we hide it here so as we translate the expression we don't
/// accidentally translate the rest of the stuff!
/// </summary>
/// <param name="expression"></param>
/// <returns></returns>
protected override Expression VisitLambda <T>(Expression <T> expression)
{
var popers = (from a in expression.Parameters
select _context.Remove(a.Name)).ToArray();
var result = base.VisitLambda(expression);
foreach (var p in popers)
{
p.Pop();
}
return(result);
}