Template:Collapsible option/doc

provides a standardised message for transclusion on the pages of collapsible templates whose collapsibility may be managed by the parameter state.

It may be used on either the template page itself (wrapped within  tags) or on the template's.

Indicating optional use of state name
The state parameter used to manage collapsible templates need not always be named explicitly, i.e. can be the same as, if the template is coded that way. To indicate this in the message, add the parameter optional. This modifies the message so that it reads (if it were used for itself):

This possibility is enabled by including: If, however, the template includes collapsible sections within itself (e.g. ), then enabling this possibility may introduce ambiguity as regards what is to be collapsed or expanded. In those instances, therefore, the requirement to use state should be retained.
 * as part of a collapsible template's state parameter – for instance, as state or state, etc.
 * , as part of a collapsible template's  argument – for instance, as state

Changing the default state
To change the default state uses, add the parameter collapsed or expanded accordingly. To restore the default, remove any default previously included.

The collapsed option must not be used in main article content in mainspace, e.g. to hide tables of information, or to cram extraneous details into infoboxes. This option permissible in navboxes, which are not part of the article content per se.

Slashes and the nobase parameter
If the template name given to includes a forward-slash (virgule) character – / – then the parameter nobase (set to on, true, etc.) will need to be added so that the name is displayed correctly (i.e., so that  rather than the default  is used to display it).