Does it make sense to work only with strings?

  Hello,

  I work with numbers and SXML trees at the same time. I don't
like to make "number->string" when putting a number to a SXML
tree and then to make "string->number" when getting the number
from the SXML tree. So I put the number into the tree as is.

  Unfortunately, I've got a problem:

[code]
;
; This works (numbers are strings)
;
(define tree
  '(*TOP*
    (item (@ (level "1")))
    (item (@ (level "3")))
    (item (@ (level "4")))))
(write ((txpath "item[@level>2]") tree))
===> ((item (@ (level "3"))) (item (@ (level "4"))))
;
; And this doesn't work (numbers are numbers):
;
(define tree
  '(*TOP*
    (item (@ (level 1)))
    (item (@ (level 3)))
    (item (@ (level 4)))))
(write ((txpath "item[@level>2]") tree))
===> ()
[/code]

  As I traced the situation, "@level>2" produces a call to

(sxml:relational-cmp <)

  with

obj1: ((level "1")) or ((level 1))
obj2: 2

  As obj1 is a nodeset, it's transformed to "nset1" as

(map (lambda (node) (sxml:number (sxml:string-value node))

  and the problem lies in "sxml:string-value":

(if (string? node)
  node
  "")  ; for XPath 1.0 it is an incorrect situation

  So my questions are:

  Is it really useful to return empty string here?

  Should I expect similar problems in other functions?


  Regards, Oleg


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