Template:LinklessExists/doc

Linkless exists checks whether a page exists. It differs from alternatives such as #ifexist: in that the page containing this template is not recorded as linking to or transcluding the page being checked. This has the advantage of avoiding spurious wikilinks, especially to disambiguation pages which should not have incoming links, but has the disadvantage that the containing page may not be updated automatically if the checked page is created or deleted later.

Usage
The template requires one parameter: the name of the page to be checked. Include a namespace where necessary. There are two other optional parameters: the text to appear if the page is present, and the text to appear if it is absent. By default, these are set to "true" and "", which evaluate as true and false respectively within expressions.

Template Data
{   "description": "Linkless exists checks whether a page exists without recording a wikilink or transclusion", "params": { "1": {           "label": "1", "description": "The name of the page to be checked", "type": "string", "required": true },       "2": {            "label": "2", "description": "The text to appear if the page is present", "type": "string", "required": false, "default": "true", "example": "page found" },       "3": {            "label": "3", "description": "The text to appear if the page is absent", "type": "string", "required": false, "default": "(blank string)", "example": "page not found" }   } }

Original taken from: wikipedia.org/wiki/Template:Linkless_exists.