Re: Labeling a tree with MetaObj.

["Denis B. Roegel" <Denis.Roegel@loria.fr>]

On Tue, Jul 03, 2001 at 12:13:32AM +0300, Tarik Kara wrote:
> Thank you very much for the nice package and the answer to my problem.
> One small comment:  It would be nice if one could also use
>
>  ObjLabel.ntreepos(Obj(t))(btex $o$ etex) "labpathid(1)","labdir(lft)"; 
>
> In addition to
>
>  ObjLabel.Obj(t)(btex $o$ etex) "labpathid(1)", "labdir(lft)";
>
> Just for the sake of symmetry between a tree and its subtrees: The same
> idea as to get the "treeroot" function to work with an empty argument.

This is not easily possible, maybe even impossible, because
ntreepos expects two arguments. However, it is possible to write
a macro Ntreepos such that

 Ntreepos(t)
 Ntreepos(t,1)
 Ntreepos(t,1,1)
 Ntreepos(t,1,2,1)

etc., are accepted. Here Ntreepos takes one argument, which is a list
of numbers (t is also a number).
This would restore the symmetry, and even make it easier to use!
(And actually treeroot can also be simplified along these lines!)

I'll probably write such a macro for the next version, but I'll keep
the current ones for compatibility.

I am sure other things can be simplified. The problem is that I still want
to keep the package as general as possible.

Thanks for your comments!

Denis