Pages with template loops

Many pages end up here because:

1. A bug with Mediawiki causes the use of #ifexist to display the tested page in Special:WantedPages
2. The solution to the above bug Template:Exists (original source) causes a further bug due to the transclusion making the page falsely declare a template loop, where none exists.

This can be seen in any page using Template:ACS Item or Template:ACS Plant, where the Type template parameter uses this function to check for pages.

To bypass this bug, move the Type parameter exhibiting issues to the lower section below the code.