[basex-talk] increment a variable only when a conditional is true?

19 Feb 2020

      How can I increment the x variable only when numerical is false?  (I've 
been reading how xquery isn't iterative...)

current output:

<xml>
   <person id="1" x="0" numerical="false">people</person>
   <person id="2" x="0" numerical="false">joe</person>
   <person id="3" x="0" numerical="true">phone1</person>
   <person id="4" x="0" numerical="true">phone2</person>
   <person id="5" x="0" numerical="true">phone3</person>
   <person id="6" x="0" numerical="false">sue</person>
   <person id="7" x="0" numerical="true">cell4</person>
   <person id="8" x="0" numerical="true">home5</person>
   <person id="9" x="0" numerical="false">alice</person>
   <person id="10" x="0" numerical="true">atrib6</person>
   <person id="11" x="0" numerical="true">x7</person>
   <person id="12" x="0" numerical="true">y9</person>
   <person id="13" x="0" numerical="true">z10</person>
</xml>

desired output:

<xml>
   <person id="1" x="1" numerical="false">people</person>
   <person id="2" x="2" numerical="false">joe</person>
   <person id="3" x="2" numerical="true">phone1</person>
   <person id="4" x="2" numerical="true">phone2</person>
...
</xml>

Maybe with a second xquery?  Here's the first:

xquery version "3.0";

<xml>

{
variable $x:=0;

for $line in db:open("foo.txt")//text()

count $id

return    if (matches($line, "[0-9]"))
          then <person id='{$id}' x='{$x}' numerical="true">{$line}</person>
          else <person id='{$id}' x='{$x}' 
numerical="false">{$line}</person>
}
</xml>

where I'm trying to use attributes because I'm not sure how to 
conditionally nest tags.  But, this is interesting.  Not quite sure on 
syntax to set and then conditionally increment $x, however.

thanks,

Thufir

[basex-talk] increment a variable only when a conditional is true?

thufir