Template:Ifparadef/doc

This template is used to test if a parameter is defined; thus, it should only be directly used on other templates.

Usage
This template accepts up to four unnamed parameters.
 * Standard functionality:
 * Extended functionality:

The first parameter, which is required, is the name of the parameter to be tested. It must be formatted as, with the not sign (¬), otherwise the template will not work correctly (see the Examples section below for examples with and without the not sign).

The second parameter is the text to display if the tested parameter is defined, and defaults to "Defined". If the fourth parameter is also used, the second parameter is the text displayed when the tested parameter is defined and not empty, and defaults to "Defined, not empty".

The third parameter is the text to display if the tested parameter is not defined, and defaults to "Not defined".

The fourth parameter is the text to display if the tested parameter is defined and empty (or if it contains only whitespace). If this parameter is omitted, only one defined test is performed, and the contents (or default) of the second parameter are used as long as the tested parameter is defined.

This template uses a not sign (¬) to test for a defined parameter; the template cannot detect when a literal not sign is passed as input from a final deployment (such as an article) and will give incorrect results in such cases.