View source for Template:Item/doc

{{Documentation subpage}}
{{lua|Module:Item}}
This template packs structured data into a compact item, which can be passed as a parameter to another template. This allows to pass multiple structured items to that template, which can iterate over the items and extract data from them.

== Usage ==
The structured data item contains all parameters (both numbered ones and named ones) passed to the {{tl|Item}} template. For example, <code>{{tlp|Item|Alice|Bob|best{{=}}Eve}}</code> creates an item with components {{code|1{{=}}Alice}}, {{code|2{{=}}Bob}}, {{code|best{{=}}Eve}}.

Multiple items will be passed to an example recipient template {{tlu|User:Petr Matas/sandbox/Pets}} like this:
{{Automarkup|1=
{{((}}User:Petr Matas/sandbox/Pets{{!}}owner=Bob
{{!}} {{((}}Item{{!}}name=Tom{{!}}animal=cat{{!}}legs=4{{))}}
{{!}} {{((}}Item{{!}}name=Jerry{{!}}animal=mouse{{!}}legs=4{{))}}
{{!}} {{((}}Item{{!}}name=Tweety{{!}}animal=bird{{!}}legs=2{{))}}
{{))}}
}}

== Constructs available to recipient templates ==
=== Get a component of an item ===
See [[Template:Component]].

=== Format an item using a template ===
See [[Template:Format item]].

=== Format each item using a template ===
In the recipient template, use:
 {{((}}#invoke:Item|each|template=''TransformationTemplate''|''Separator''|''Prefix''|''Suffix''|...}}
This transforms all items using a given template. <code>''TransformationTemplate''</code> is called for each item with the parameters that the item has been created with, plus any additional parameters passed to {{code|#invoke}} (see {{tl|Format item}} for details). The transformed items are separated with <code>''Separator''</code> and surrounded with <code>''Prefix''</code> and <code>''Suffix''</code> (whitespace is not stripped from these three optional parameters).

The template {{tlu|User:Petr Matas/sandbox/Pets}} from the example produces the list of pets using the following code (note the use of newline as a <code>''Separator''</code> and {{code|*}} as a <code>''Prefix''</code> to produce list items):
 {{((}}#invoke:Item|each|template=[[Template:Show pet|Show pet]]|
 |*}}

=== Gather given parameter from all items ===
In the recipient template, use <code>{{((}}#invoke:Item|gather|parameter=''ParameterName''|template=''TransformationTemplate''}}</code> to gather the given parameter from all items. <code>''TransformationTemplate''</code> will be called ''once'' and the gathered parameters (one parameter from each item) will be passed to it.

The template {{tlu|User:Petr Matas/sandbox/Pets}} from the example produces the total number of legs using <code>{{((}}#invoke:Item|gather|parameter=legs|template=[[Template:Sum|Sum]]}}</code>.

== See also ==
* {{tl|For loop}}
<includeonly>{{Sandbox other||
[[Category:Wikipedia formatting and function templates]]
}}</includeonly>