Template:Allbooks category/core2
This template implements the final phase of internal processing for template {{Allbooks category}}. On entry here, we already know the subject page exists and is correctly formatted for extraction of its parameters.
Usage
There are three parameters, assumed to be specified (even if blank).
parent— the name of a parent subject, or blank.parent2— the name of a parent subject, or blank.subject— the name of the subject associated with this allbooks category; just the name of this category without the "/all books" suffix.
This template attempts to add this allbooks category to the allbooks categories associated with the parent subjects, via {{Allbooks category/parent}}, and provides a notice that this allbooks category should be populated automatically.