Template:GetCategory

Version of February 2012 - old version see Template:GetCategoryOLD

The template takes one parameter, the name of a page (e.g. the page name of a pest, disease or weed). It determines the first higher category of this page name and returns it, if any exist. For crops a different procedure is used, see Template:GetCategory2.

The template uses the following procedure:

1. It checks for higher categories of the page name using "{{#ask:[[<page name>]]|?Category=|link=none|format=list}}". This will only return a category if <page name> is a normal page and not a category itself. However, <page name> may be redirected to a normal page. The result may be several categories, separated by commas.
2. If several categories are found, only the first category is used. In this case it is checked if this is a valid pagename.
3. The value may be blank, if no (valid) category is found.

Note:
The result of the above category query has changed repeatedly since 2010. For SMW Version 1.6.2 the query

{{#ask:[[Helicoverpa zea]]|?Category=|link=none|format=list}}

gave the result "Category:Helicoverpa (genus)". Since Version 1.7 it gives "Helicoverpa zea (Category:Helicoverpa (genus))".

The template has the following structure:

1. Define the variable "CategoryTemp" as the result of the query for categories of the pagename and the variable "Category" as an empty string:
{{#vardefine:CategoryTemp|{{#ask:[[{{{1}}}]]|?Category=|link=none|format=list}} }}{{#vardefine:Category|}}

2. If the query result is not empty....
{{#if:{{#var:CategoryTemp}}|

   3. define the variable "Position1" which is used to determine if a category was found
   {{#vardefine:Position1|
      {{#pos:{{#var:CategoryTemp}}|(Category:}}
   }}

   4. A category is found...
   {{#if:{{#var:Position1}}|

   5. define the variable "Position2" which the position of the next comma
   {{#vardefine:Position2|
      {{#pos:{{#var:CategoryTemp}}|,|{{#var:Position1}}}}
   }}

       5a. if a comma was found define variable "Category" as the text between
            "(Category:" and the comma
       {{#if:{{#var:Position2}}|
         {{#vardefine:Category|
            {{#sub:{{#var:CategoryTemp}}|{{#expr:{{#var:Position1}}+10}}|
               {{#expr:{{#var:Position2}}-{{#var:Position1}}-10}}}}
         }}

      5b. if a comma was not found define variable "Category" 
         as the remaining text minus the last ")"
      |
         {{#vardefine:Category|
            {{#sub:{{#var:CategoryTemp}}|{{#expr:{{#var:Position1}}+10}}|
               {{#expr:{{#len:{{#var:CategoryTemp}}}}-{{#var:Position1}}-11}}}}
         }}

      }} (end of "{{#if:{{#var:Position2}} ...")

   }} (end of "{{#if:{{#var:Position1}} ...")

}} (end of "{{#if:{{#var:CategoryTemp}} ...")

6. return the variable "Category"
{{#var:Category}}