Template:If then show
 | This template is used on approximately 319,000 pages, or roughly 1% of all pages. To avoid major disruption and server load, any changes should be tested in the template's /sandbox or /testcases subpages, or in your own user subpage. The tested changes can be added to this page in a single edit. Consider discussing changes on the talk page before implementing them. |
This template tests whether the first unnamed parameter is not an empty string and returns it if it is not empty. Otherwise it returns the second unnamed parameter.
This is useful when the first parameter is a {{#invoke: }} of a Lua module that may return a value or nothing. Because it uses the {{#invoke: }} just once, it simplifies the coding of infoboxes, for example.
The optional third and fourth unnamed parameters provide a prefix and a suffix for the first parameter when returned. This enables the designer to construct more complex templates that still only use one invoke of a Lua module.
Usage
- spouse (P26) for Richard Burton (Q151973)
{{If then show|{{#invoke:WikidataIB|getValue|P26|qid=Q151973|fwd=ALL|osd=no}}|unmarried}}→ Elizabeth Taylor, Sybil Christopher, Suzy Miller, Elizabeth Taylor, Sally Burton
- spouse (P26) for Franz Kafka (Q905)
{{If then show|{{#invoke:WikidataIB|getValue|P26|qid=Q905|fwd=ALL|osd=no}}|unmarried}}→ unmarried
Prefix and suffix
Infobox field with microformat
A value in an infobox can be designed to be wrapped in a microformat if the wikidata call is not empty:
{{if then show | {{#invoke:WikidataIB | getValue | rank=best |P19 |name=birth_place |qid={{{qid|}}} |suppressfields={{{suppressfields|}}} |fetchwikidata={{{fetchwikidata|}}} |noicon={{{noicon|}}} | {{{birth_place|}}} }} || <span class="birthplace"> | </span>}}- If there is a local parameter supplied in the article (e.g.
|birth_place=London), the code will return<span class="birthplace">London</span>. - If there is no local parameter it will attempt to fetch a value for place of birth (P19) from Wikidata.
- If that has a value, such as "New York", the code will return
<span class="birthplace">New York</span>. - If there is no value returned from Wikidata, the code returns nothing.
Table
A table can be designed to display a row only when a particular property of the article exists on Wikidata.
- spouse (P26) for Richard Burton (Q151973)
{| class="wikitable" |- ! scope="col" style="width:15em;" | Label ! scope="col" style="width:36em;" | Value {{If then show|{{#invoke:WikidataIB|getValue|P26|qid=Q151973|fwd=ALL|osd=no}}||<tr><th>{{#invoke:WikidataIB|getLabel|P26|qid=Q151973}}</th><td>|</td></tr>}} |}
- →
| Label | Value |
|---|---|
| spouse | Elizabeth Taylor, Sybil Christopher, Suzy Miller, Elizabeth Taylor, Sally Burton  |
- spouse (P26) for Franz Kafka (Q905)
{| class="wikitable" |- ! scope="col" style="width:15em;" | Label ! scope="col" style="width:36em;" | Value {{If then show|{{#invoke:WikidataIB|getValue|P26|qid=Q905|fwd=ALL|osd=no}}||<tr><th>{{#invoke:WikidataIB|getLabel|P26|qid=Q905}}</th><td>|</td></tr>}} |}
- →
| Label | Value |
|---|
See also
- Template:Ifnoteq then show
- tests whether the first unnamed parameter is equal to the second unnamed parameter and returns the third unnamed parameter if it does. Otherwise it returns the first unnamed parameter. This is useful when the first parameter is a
{{#invoke:of a Lua module that returns a value for which a specific exception is required. - Template:If then wikilink
- tests whether the first unnamed parameter is not an empty string and if it isn't, it returns the parameter formatted as piped wiki-link using an optional namespace prefix.
- Template:Formatter link
- takes an external identifier code as
|code=and uses a formatter url as|url=to construct a link to the external resource, which uses the code as display. - Template:Emptyor
- tests a piece of text to ascertain whether it's effectively empty or contains some text. If the unnamed parameter consists only of html tags, punctuation (e.g. Wiki-markup) and whitespace, then Emptyor returns nothing; otherwise it returns the parameter unchanged. Wrapper for p.emptyor function.