[pooma-dev] Compile Time Problems and Pooma 2

[Scott Haney]

On Tuesday, May 29, 2001, at 02:12 PM, Dave Nystrom wrote:

>
> What I hear you saying is that you don't think you can guarantee that 
> Pooma 2
> can be written in a way that guarantees no circular dependencies.  Is 
> that
> really true?  I've read books that claim that circular dependencies are 
> bad
> and indicate deficiencies in the software design.  And I confess that I 
> tend
> to believe them.  But I am not sufficiently proficient at C++ software 
> design
> to make any kind of absolute statements on this topic and as I have 
> indicated
> I do not know enough about the details of Pooma 2 to really know what 
> you
> guys are up against when it comes to trying to meet your design goals 
> for
> Pooma 2.  But, I thought that you solved a similar type of problem with 
> the
> Array class.  Did Jeffrey take the same approach that you did with the 
> Array
> class or is his solution somewhat different?  I did not follow his 
> solution
> very closely - I was just hoping that you guys would know how to fix the
> problem and I could then update my Pooma 2 and continue on with the 
> explicit
> instantiation stuff.
>

Dave,

As a general principle, we can agree that circular dependencies are bad. 
Field is using auxiliary templates that need information from Field. 
This problem can be worked around nicely in non-templated C++ code, but 
it is difficult to work through with templates. However, maybe, by 
re-factoring, this can be fixed. In particular, AltView1 doesn't use 
that much of Field. I will give this a shot.

Scott