Template:If empty

This template is used on many pages and changes may be widely noticed.

Test changes in the template's /sandbox or /testcases subpages, or in your own user subpage.
Consider discussing changes on the talk page before implementing them.

This template was ported from a template from Wikipedia. It was originally at Template:If empty. The original authors of this template are shown on the template's edit history page.
This template's documentation was also ported from Wikipedia, originally from Template:If empty/doc. The original authors of the documentation are shown on the documentation's edit history page.
Wikipedia's text is available under the Creative Commons Attribution-ShareAlike 3.0 Unported License.

Template Documentation [編輯] [ 建立 ]

 Available doc translations

…

Subpages

Strings

Sandbox

Testcase

 English

 中文（臺灣）

The Template:If empty/doc/zh-tw documentation page does not exist.
English documentation will be displayed instead, which you can translate using Google Translate (or similar software). If there is nothing after this message, most likely the documentation does not exist even in English.

This is the {{ifempty}} template.

This template is used inside other templates. It takes up to nine parameters (parameters 1-9), and returns the first one that is defined and non-empty, otherwise nothing. Typical usage is like this:

{{ifempty| {{{logo|}}} | {{{image|}}} | default.svg }}

This returns the first of the parameters logo and image that is defined and non-empty, otherwise "default.svg".

Background

The MediaWiki parameter default function doesn't return the default value for empty parameters. That is, {{{logo|default.svg}}} does not return "default.svg" if the template was called like this: {{template|logo=}}.

The usual workaround is to do like this:

{{#if:{{{logo|}}}| {{{logo}}} | default.svg }}

But this becomes complex when you want to check several parameters:

{{#if:{{{logo|}}}| {{{logo}}} | {{#if:{{{image|}}} | {{{image}}} | default.svg }}}}

Then it is easier to use this template instead:

{{ifempty| {{{logo|}}} | {{{image|}}} | default.svg }}

Note! The parameters to {{ifempty}} must use the pipe "|", like this: {{{logo|}}}. Or else {{ifempty}} will be fed and return the string "{{{logo}}}" if logo was not defined.

Examples

Code	Result	Comment
{{ifempty}}		Returns an empty string.
{{ifempty|one}}	one	Returns the first parameter that is defined and not empty.
{{ifempty|one|two}}	one
{{ifempty|one|two|three|four}}	one
{{ifempty||two}}	two	The first parameter was empty or undefined, so uses the next parameter.
{{ifempty||two|three|four}}	two
{{ifempty||two||four}}	two
{{ifempty|||||||||nine}}	nine
{{ifempty||||||||||ten}}		Only handles up to nine parameters, so returns an empty string.
{{ifempty|}}		The only parameter is empty or undefined, so returns an empty string.
{{ifempty||||}}		Returns an empty string.
{{ifempty|{{{1|}}}|{{{2|}}}|three}}	three
{{ifempty|{{{1}}}|{{{2}}}|three}}	{{{1}}}	Returns the text "{{{1}}}", because it is a non-empty string. Note the lack of "|" in the first two parameters.
{{ifempty|{{{logo|}}}|two}}	two
{{ifempty|{{{logo}}}|two}}	{{{logo}}}	Returns the text "{{{logo}}}", because it is a non-empty string. Note the lack of "|" in the first parameter.
{{ifempty|2=x}}	x	Whether parameter 1 is undefined or empty does not matter.
{{ifempty|p=q}}		The template checks its parameters 1-9, not other ones.

See also

• {{If all}}
• {{If either}}

• {{px}} – Helps handling image width parameters in templates.
• Help:Parameter default – You probably don't need to know this anymore if you use this template.