Template:ARTICLEROOTPAGENAME/doc

Returns the associated content namespace (e.g. "Template" if used on a page in the "Template" or "Template talk" namespace), followed by the root of the page name in namespaces where automatic subpages are enabled or the full page name otherwise. It is equivalent to {{ARTICLESPACE}}:{{ROOTPAGENAME}}, with an additional {{#if:}} statement to avoid adding a colon on regular pages.