<?php
class CategoryByListHooks {
   // Register any render callbacks with the parser
   public static function onParserFirstCallInit( Parser $parser ) {

      // Create a function hook associating the "example" magic word with CategoryByList()
      $parser->setFunctionHook( 'CategoryByList', [ self::class, 'CategoryByList' ] );
   }

   // Render the output of {{#example:}}.
   public static function CategoryByList( Parser $parser, $param1 = '', $param2 = '', $param3 = '' ) {

      // The input parameters are wikitext with templates expanded.
      // The output should be wikitext too.
      $output = "";

      $categories = explode(', ', $param1);
      foreach ($categories as $item) {
        $output .= '[[Categoría:'.$item.']]';
      }

      return $output;
   }
}