I'm working through some Qt code, and there are a bunch of places you find include guards like:
Qt Code: 
  1. #ifndef QT_NO_ITEMVIEWS
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I'm curious what the 'NO' means here? At first I thought it meant 'no', like 'no item views allowed'. Obviously that is silly. This nomenclature is used for every feature. List of such features is found here:
http://realxtend-naali-deps.googleco...re/qfeatures.h
http://code.metager.de/source/xref/l.../qfeatures.txt
They are defined here:
https://github.com/openwebos/qt/blob...features_dot_h

I've searched some, and cannot find what this NOmenclature means. Likely an acronym, but for what?