How do I reuse an Expression on a single object in another Expression

Question

I feel like I am missing something simple, but I have not found the documentation that answers my question.

I have recently been decomposing some of the linq projection

Answer 1

You can use LINQKit to expand the expressions that you have within other expressions:

private static Expression> CreateDepartmentDtoUnexpanded = d => new DepartmentDto
{
    Manager = CreatePersonDto.Invoke(d.Manager),
    Employees = d.Employees.Select(employee => CreatePersonDto.Invoke(employee))
        .ToList(),
};
public static Expression> CreateDepartmentDto = CreateDepartmentDtoUnexpanded.Expand();