Re: Desperate Questions: [1]Absolute-Child-Number

[Vivek Agrawala <vivek@xxxxxxxxxxxxxxx>]

W. Eliot Kimber wrote:

> My first challenge is calculating the absolute child number of an element.
> The standard DTD has 7 different element types that are the first level
> divisions within standard (H1, scope, refs, defs, notation, annexn,
> annexi).  In order to number things automatically I need the absolute child
> numbers of these element types.  However, I can't for the life of me figure
> out how to do it.  Here's my attempt at an absolute-child-number function:
> 
> (define (absolute-child-number %element%)
>   (- (node-list-length (children (parent %element%)))
>      (length (member (node-list->list %element%) (node-list->list (children
> (parent %element%)))))))
> 


How about something like this:

;; loop through the siblings of %element% till you find %element%
;; and return its position number
 (define (absolute-child-number %element%)
   (let loop ((siblings (children (parent %element%)))
              (i 0) )
     (cond
       ((node-list-contains? (node-list-first siblings) %element%) i)
       ((node-list-empty? siblings) -1)  ;; error!
       ( else (loop (node-list-rest siblings) (+ i 1) ))))

Note that I just wrote this & haven't tested it!

-- Vivek Agrawala, Ph.D.
Siemens Corporate Research, Inc.	email: vivek@xxxxxxxxxxxxxxx

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