expression.cs

        private static IEqualityComparer<T> GetInstance()
        {
            var type = typeof(T);
            ParameterExpression[] parameters =
            {
                Expression.Parameter(type, "x"),
                Expression.Parameter(type, "y")
            };

            var result = type.GetProperties().Aggregate<PropertyInfo, Expression>(
                Expression.Constant(true),
                (acc, prop) =>
                    Expression.And(acc,
                        Expression.Equal(
                            Expression.Property(parameters[0], prop.Name),
                            Expression.Property(parameters[1], prop.Name))));
            var expr = Expression.Lambda<Func<T, T, bool>>(result, parameters);
            var equalFunc = expr.Compile();
            return new DelegateEqualityComparer(equalFunc);
        }