[basex-talk] "Expressions must be all updating" puzzle

19 Aug 2023

      In BaseX 10:

In an updating function I have a call to another updating function that uses update:output()  to log messages.

If that function call is included, BaseX says that expressions must be all updating, but if I remove the call, BaseX is happy.

The calling function is:

declare %updating
  %rest:path('/now/rest/analytics/store-latest-acrolinx-users' )
function now:storeAcrolinxUsers() {
  let $acrolinxMap as map(*)? :=
    try {
      acrolinx:getUserDataMap()
    } catch * {
      util:logToConsole(
        'storeAcrolinxUsers'
        ,``[`{$err:code}` - `{$err:description}`]``
        ,'warn'
      )
    }
  return
  if (exists($acrolinxMap))
  then
  let $doc as element() := acrolinx:serializeAcrolinxUserMap($acrolinxMap)
  let $fileName as xs:string := 'acrolinx-users_' || replace($doc/@timestamp, ':', '~') || '.xml'
  return db:put(analyticsmgmt:getAnalyticsDatabase(), $doc, relpath:newFile('acrolinx/users', $fileName))

};

The offending function is util:logToConsole(), which is declared as:

declare %updating function util:logToConsole(
  $functionName as xs:string,
  $message as xs:string,
  $logLevel as xs:string
) {
  let $logMessage as xs:string := '[' || upper-case($logLevel) || '] ' || $functionName || '(): ' || $message
  return
  (
    update:output(prof:dump($logMessage)) ,
    update:output($logMessage)
  )
};

This is declared as an updating function and returns “updating” functions.

If I comment out the call to util:logToConsole() in the first function, then BaseX is happy.

If I use the non-updating version of logToConsole(), util:logToLog(), then BaseX is also happy.

So my question is: why is BaseX complaining about the use of this updating function in an updating function?

There must be some subtlety that I’m missing but I have not yet figured out what it is.

Thanks,

Eliot
_____________________________________________
Eliot Kimber
Sr Staff Content Engineer
O: 512 554 9368
M: 512 554 9368
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