Template:Subject category/core
<there is no corresponding subject page Subject:{{{subject}}}>
This template implements the initial phase of internal processing for template {{Subject category}}. On entry here, all that is known is the name of the subject.
Usage edit
There is one parameter, assumed to be specified and non-blank.
subject— the name of the subject. NoSubject:prefix.
This template checks that the subject page exists and is correctly formatted for extracting its parents. If all is well, extracts the parents from the subject page and calls {{subject category/core2}}.