I had an xs:boolean data type which remained unresponsive to 0, 1, false, true, "false", and "true" values.  In other words, the transformation was not evaluating these values correctly (or at all) in my XML parser transformation.

Data originated from a SOAP call, which had a related WSDL definition in a text file.

I manually changed (i.e. hacked) underlying WSDL to use xs:string - and then "true" and "false" started working as expected.

The unmodified WSDL in SoapUI did not show the same problem - it worked as expected with xs:boolean.

I was therefore unable to get any data out of a XML Parser transformation - which, ironically, had been created in PowerCenter by importing the very data I was not able to parse.  An obscure (to me) setting held the key.

See the “Advanced Options…” link below:

This controls how namespace labels are added (or not added) to XML tags. Setting this to “no” solved my problem - but I don’t know if there may be other unintended consequences down the line.