Editing Template:Templatedata header/doc (section)

==Example==
:Using a collapse box for {{elc|Template:User}}:
{{nowiki template demo|code=<nowiki>
{{collapse top|title=TemplateData}}
{{TemplateData header|User}}
<templatedata>
{
	"description": "This template is used to create a link to a user's user page (unless using {{Useranon}}), talk page, and contributions, and generates a special notification (aka 'ping').",
	"params": {
		"1": {
			"label": "User name",
			"type": "string",
			"required": true,
			"description": "The user name that you want to create links to and notify.",
			"aliases":["user"]
		},
		"project": {
			"label": "Sister project",
			"type": "string",
			"description": "Used to link to a sister project instead of the English Wikipedia. Use the standard interwiki prefix."
		},
		"lang": {
			"label": "Other language project",
			"type": "string",
			"description": "Used to link to another language project. If used with the \"sister project\" parameter, links to another language of a sister project. Otherwise links to another language Wikipedia. Use the standard language code."
		},
		"separator": {
			"label": "Separator",
			"description": "Used to change the separator between the links. If unused, defaults to a dot."
		}
	}
}
</templatedata>
{{collapse bottom}}</nowiki>}}