Upgrading to 3.0

Well, we are about to take the leap next week and upgrade to 3.0

I have reviewed the ChangeLog, and there are was one thing that does not look backwards compatible:

Renamed FindOne(object) overload to FindById

Are there any other cadveats that we should be aware of?

Thanks,

-Joe

I've had a blog post lined up on this very subject and this seems the ideal moment to release it!

http://www.mindscape.co.nz/blog/index.php/2009/12/17/moving-from-lightspeed-2-to-lightspeed-3/

We believe these should be the only compatibility concerns.

perfect timing! thanks...

There's the datacontract serialization breaking change mention in my other thread.

Also LS3 linq doesn't seem to support invocationexpressions, or at least I had to rewrite a bunch of our code that builds queries to not use Expression.Invoke to make it work with LS3.

Hi Luke,

Would you be able to provide us with an example of Expression.Invoke that worked on LightSpeed 2.x but fails on LightSpeed 3?  Thanks!

We have expression extension helper methods like these

        public static Expression<Func<T, bool>> Or<T>(this Expression<Func<T, bool>> expr1, Expression<Func<T, bool>> expr2)

        {

            var invokedExpr = Expression.Invoke(expr2, expr1.Parameters.Cast<Expression>());

            return Expression.Lambda<Func<T, bool>>(Expression.OrElse(expr1.Body, invokedExpr), expr1.Parameters);

        }

        public static Expression<Func<T, bool>> ValueEquals<T, TValue>(Expression<Func<T, TValue>> expression, TValue value)

        {

            var x = Expression.Parameter(typeof(T), "x");

            var binEx = Expression.Equal(Expression.Invoke(expression, x), Expression.Constant(value));

            return Expression.Lambda<Func<T, bool>>(binEx, x);

        }

Those work with LS2 but not LS3. I got them to work with LS3 by not using .Invoke and doing a whole parameter-copy-with-a-tree-visitor thing.