Recreating length-specs

[Richard Light <richard@xxxxxxxxxxxxxxxxx>]

Hi,

When time permits I'm looking into this FOT identity transform issue
(well, I don't hear anyone else offering a working solution!), and I'm
getting stuck with (display-space).

The space-before characteristic is of this type, which is constructed by
the (display-space) procedure:

(display-space length-spec #!key min: max: conditional?: priority:)

I've written a procedure that attempts to take the three attributes that
Jade outputs and recombine them into a display-space, but I'm falling at
the first hurdle.  This is the error I get:

C:\DSSSL\JADE\JADE.EXE:fotasis.dsl:88:4:E: 1st argument for primitive
"display-space" of wrong type: "6000" not a length or length-spec

and this is my procedure:

(define (atts-to-display-space attname attmin attmax)
  (if (attribute-string attname (current-node))
    (display-space
      (string->number (attribute-string attname (current-node)))
      min: 0m max: 0m conditional?: #t priority: 0)
    (display-space 0m min: 0m max: 0m conditional?: #t priority: 0)))

The problem is that in my FOT input, the length-specs have been
converted to dimensionless quantities, e.g.:

<paragraph space-before.min=6000 ...

How do I convert them back?  There is a (quantity->number) procedure,
but not (number->quantity).

Also, in what dimensions is the FOT output expressed?

Richard Light.

Richard Light
SGML/XML and Museum Information Consultancy
richard@xxxxxxxxxxxxxxxxx


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