View source for Template:Excerpt/doc

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{{seealso|Template:ExcerptHeaderLevel}}
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{{High-use}}
This template is used for reusing parts of pages in other pages. This practice has various [[#Advantages and disadvantages|advantages and disadvantages]].

This template extends the capabilities of the built-in [[Help:Transclusion|normal transclusion]] and [[Help:Labeled section transclusion|labeled section transclusion]].

== Usage ==

* <code><nowiki>{{Excerpt|Page title}}</nowiki></code> – Transclude the lead section ([[Africa#Architecture|example]])
* <code><nowiki>{{Excerpt|Page title|Section title}}</nowiki></code> – Transclude a specific section, excluding any subsections ([[Eating#Mammals|example]])

== Parameters ==

There is one required parameter, and numerous optional ones for configuring the excerpt:

=== Summary ===

'''Source identification'''

* {{para|1}} – Name of the article or page to transclude. '''Required.''' Aliases: {{para|article}} or {{para|page}}. 
* {{para|2}} – Name of the section or tag to transclude. Optional; if omitted, transcludes the lead section (content above the first section header). Aliases: {{para|section}} or {{para|fragment}}.

'''Transclusion config'''

Transcludable content is defined as one of several ''element types'': {{pval|file}}, {{pval|gallery}}, {{pval|list}}, {{pval|paragraph}}, {{pval|reference}}, {{pval|subsection}}, {{pval|table}}, or {{pval|template}}. 
Config parameters specify which ''element type'' to transclude, and in some cases, ''how many'' and ''which'' items of that type to transclude. All config parameters are optional; if omitted, all items of all element types are transcluded from the source page identified by the two unnamed parameters. Some element types support conditional item transclusion by specifying an item number range (1-3) or comma series (1, 2, 5); these types include: files, galleries, lists, paragraphs, and tables.

There are nine optional transclusion configuration parameters (which may all be used in singular or plural alias form):

* {{para|only}} – Element types to transclude. Values: {{pval|file(s)}}, {{pval|gallery(-ies)}}, {{pval|list(s)}}, {{pval|table(s)}}, {{pval|template(s)}}, {{pval|paragraph(s)}}. Default: all element types.
* {{para|files}} – [[WP:FILE|Files]] to transclude. Default: all files. Same basic syntax as {{para|paragraphs}}, but see {{slink||Details}}.
** {{para|onlyfreefiles|no}} – Enables transclusion of [[WP:Non-free content|non-free files]]. Default: exclude non-free content.
* {{para|galleries}} – [[Help:Gallery tag|Galleries]] to transclude. Default: all galleries. Same syntax as {{para|paragraphs}}; see {{slink||Details}}. (Alias: {{para|gallery}}.)
* {{para|lists}} – Lists ([[MOS:LIST#Bulleted lists|bulleted]], [[MOS:LIST#Numbered lists|numbered]]) to transclude. Default: all lists. Same syntax as for {{para|paragraphs}}.
* {{para|paragraphs}} – [[H:PARAGRAPH|Paragraphs]] to transclude. Default: all paragraphs.
* {{para|references|no}} – Exclude all [[WP:REF|references]] between <code><nowiki><ref>...</ref></nowiki></code> tags.
* {{para|subsections|yes}} – Include [[MOS:SECTIONS|subsections]] of the transcluded section. Default: only content above the first subsection header.
* {{para|tables}} – [[Help:Table|Tables]] to transclude. Default: all tables. Same basic syntax as {{para|paragraphs}}, but see {{slink||Details}}.
* {{para|templates}} – [[Help:Template|Templates]] to transclude. By default all templates are transcluded, except those blacklisted at [[Module:Excerpt/config]]. See {{slink||Details}} for how to specify a specific template or templates for inclusion or exclusion.

'''Style and extra features'''

These optional parameters alter the way transcluded items are displayed:

* {{para|bold|yes}} – Preserve '''bold''' text.
* {{para|briefdates|yes}} – Abbreviate birth and death information to (YYYY-YYYY) format
* {{para|displaytitle}} – Change the text of the link in the hatnote. For example, [[WP:ITHAT|add italics]], subscripts, etc.
* {{para|hat|no}} – Hide the [[Wikipedia:Hatnote|hatnote]] "This section is an excerpt from...". See param {{para|this}} below, to modify the hatnote wording.
* {{para|inline|yes}} – Remove the <code><nowiki><div></nowiki></code> tags around the excerpt, to use it inside other text, or to add references or other content after it [[#Suppress line breaks between paragraphs|with no paragraph break]] between them. Also hides the hatnote; to reestablish it, use {{tl|transclusion notice}} above the Excerpt invocation.
* {{para|links|no}} – Unlink all [[H:WIKILINK|wikilinks]] and render as plain text.
* {{para|quote|yes}} – Wrap the excerpt with <code><nowiki><blockquote></nowiki></code> tags.
* {{para|this}} – Change the initial text of the hatnote. For example, if the transcluded content is a gallery, you can set {{para|this|This gallery is}} so that the hatnote reads "This gallery is an excerpt from..." (default: "This section is").

=== Details ===

* {{para|1}} or {{para|article}} or {{para|page}}
*: By default the lead section is transcluded ([[Africa#Water|example]]). If the page contains an infobox, the image and caption of the infobox will be transcluded (unless {{para|files|0}} is set). Also, templates listed at [[Module:Excerpt/config]] will not be transcluded (unless requested explicitly with {{para|templates}}, see below).
* {{para|2}} or {{para|section}} or {{para|fragment}}
*: Name of the section to transclude ([[Eating#Mammals|example]]) or of the <code><nowiki><section></nowiki></code> tag to transclude ([[Axiom Space#Ax-1|example]]). In the case of a section tag, the section must be marked with <code><nowiki><section begin="Name of the fragment" /></nowiki></code> and <code><nowiki><section end="Name of the fragment" /></nowiki></code> in the page to be transcluded. Notice that this template provides other ways of targeting specific fragments of a page without having to resort to section tags.
* {{para|only}}
*: The ''element type'' to transclude, excluding all other types. By default all element types are transcluded. Param {{para|only}} is an exclusionary param, and excludes all other types of elements, except the one you name, so that for example, specifying {{para|only|paragraphs}} excludes all lists, tables, templates, and so on. Param values can be in the singular (e.g., {{para|only|paragraph}}) or plural (e.g., {{para|only|paragraphs}}) and mean different things: in the singular, only the first item of that element type is transcluded; in the plural, all items are. 
*:* {{para|only|file}} – Transclude only the first file (but no lists, paragraphs, tables, etc.)
*:* {{para|only|files}} – Transclude all files (but nothing else)
*:* {{para|only|filename}} – Transclude only the file name (Example.jpg) of the first file (and nothing else). If no file is found, "Noimage.png" will be returned.
*:* {{para|only|gallery}} – Transclude only the first gallery, exclude all other element types
*:* {{para|only|galleries}} – Transclude all galleries (but nothing else)
*:* {{para|only|list}} – Transclude only the first list, exclude all other element types
*:* {{para|only|lists}} – Transclude all lists (but nothing else)
*:* {{para|only|table}} – Transclude only the first table, exclude all other element types. Does not transclude table templates, use {{para|templates}} for that.
*:* {{para|only|tables}} – Transclude all tables (but nothing else)  ([[JKT48#Singles|example]]) 
*:* {{para|only|template}} – Transclude only the first template (excluding templates blacklisted at [[Module:Excerpt/config]], as well as all other element types)
*:* {{para|only|templates}} – Transclude all templates (excluding blacklisted templates) (but nothing else) 
*:* {{para|only|paragraph}} – Transclude only the first paragraph, exclude all other element types
*:* {{para|only|paragraphs}} – Transclude all paragraphs (but nothing else)
* {{para|files}}
*: An ''element item'' param, defining which files, such as images and other media, to transclude. Default: all files. 
*:* {{para|files|0}} – Transclude no files
*:* {{para|files|1}} – Transclude the first file
*:* {{para|files|A.jpg}} – Transclude the file named 'A.jpg'
*:* {{para|files|A.jpg, B.png, C.gif}} – Transclude the files named 'A.jpg', 'B.png' and 'C.gif'
*:* {{para|files|.+%.png}} – Transclude all PNG files
*:* {{para|files|-A.jpg}} – Transclude all files except the one named 'A.jpg'
*:* {{para|files|-A.jpg, B.png, C.gif}} – Transclude all files except the ones named 'A.jpg', 'B.png' and 'C.gif'
*:* {{para|files|-.+%.png}} – Transclude all non-PNG files
* {{para|galleries}}
*: An ''element item'' param, defining which galleries to transclude. By default all galleries are transcluded.
*:* {{para|galleries|0}} – Transclude no galleries
*:* {{para|galleries|1}} – Transclude the first gallery
*:* {{para|galleries|2}} – Transclude the second gallery
*:* {{para|galleries|1,3}} – Transclude the first and third galleries
*:* {{para|galleries|1-3}} – Transclude the first, second and third galleries
*:* {{para|galleries|1-3,5}} – Transclude the first, second, third and fifth galleries
*:* {{para|galleries|-1}} – Transclude all galleries except the first
*:* {{para|galleries|-2}} – Transclude all galleries except the second
*:* {{para|galleries|-1,3}} – Transclude all galleries except the first and third
*:* {{para|galleries|-1-3}} – Transclude all galleries except the first, second and third
*:* {{para|galleries|-1-3,5}} – Transclude all galleries except the first, second, third and fifth
* {{para|paragraphs}}
*: An ''element item'' param, defining which paragraphs to transclude. By default all paragraphs are transcluded.
*:* {{para|paragraphs|0}} – Transclude no paragraphs
*:* {{para|paragraphs|1}} – Transclude the first paragraph
*:* {{para|paragraphs|2}} – Transclude the second paragraph
*:* {{para|paragraphs|1,3}} – Transclude the first and third paragraphs
*:* {{para|paragraphs|1-3}} – Transclude the first, second and third paragraphs
*:* {{para|paragraphs|1-3,5}} – Transclude the first, second, third and fifth paragraphs
*:* {{para|paragraphs|-1}} – Transclude all paragraphs except the first
*:* {{para|paragraphs|-2}} – Transclude all paragraphs except the second
*:* {{para|paragraphs|-1,3}} – Transclude all paragraphs except the first and third
*:* {{para|paragraphs|-1-3}} – Transclude all paragraphs except the first, second and third
*:* {{para|paragraphs|-1-3,5}} – Transclude all paragraphs except the first, second, third and fifth
* {{para|subsections|yes}}
*: An ''element item'' param, defining which subsections of the source to transclude. Default: only the portion of the source lying above the first subsection header. Notice that if the transclusion is done from a section level 3 in the transcluding page, and the transcluded subsections are also level 3, then transcluded subsections will show with the same hierarchy as the transcluding section, which may not be the desired outcome, so use with caution.
* {{para|tables}}
*: An ''element item'' param, defining which tables to transclude. Default: all tables. Does not transclude table templates just above the tables. Same syntax as when transcluding paragraphs, but also:
*:* {{para|tables|Stats2020}} – Transclude the table with id 'Stats2020'
*:* {{para|tables|Stats2020, Stats2019, Stats2018}} – Transclude the tables with ids 'Stats2020', 'Stats2019' and 'Stats2018'
*:* {{para|tables|-Stats2020}} – Transclude all tables except the one with id 'Stats2020'
*:* {{para|tables|-Stats2020, Stats2019, Stats2018}} – Transclude all tables except the ones with ids 'Stats2020', 'Stats2019' and 'Stats2018'
* {{para|templates}}
*: An ''element item'' param, defining which templates to transclude. Default: all templates except those blacklisted at [[Module:Excerpt/config]]. Using a hyphen (minus sign) before a comma-delimited list of templates excludes those templates from transclusion.
*:* {{para|templates|-Ocean}} – Add the template 'Ocean' to the blacklist
*:* {{para|templates|-Ocean, Nature}} – Add the templates 'Ocean' and 'Nature' to the blacklist
*:* {{para|templates|Infobox person}} – Ignore the blacklist and transclude the template 'Infobox person'
*:* {{para|templates|Infobox person, Ocean}} – Ignore the blacklist and transclude the templates 'Infobox person' and 'Ocean'
*:* {{para|templates|.*}} – Ignore the blacklist and transclude all templates

== Tips and how-to ==

=== Compared to #section ===

{{Further|Help:Transclusion#Standard section transclusion}}

For simple cases of transcluding sections of articles, the {{pf|section}}, {{pf|section-x}}, and {{pf|section-h}} (abbreviated {{pf|lst}}, {{pf|lstx}}, and {{pf|lsth}})) parser functions can be used instead of this template. {{pf|lsth|''article''|''fragmentname''}} will transclude the section of "''article''" with the header "''fragmentname''", and {{pf|lsth|''article''}} will transclude the lead section of "''article''". Excerpting only specific paragraphs can be done by marking up the source article with <code><nowiki><section begin=</nowiki>''<nowiki>fragmentname</nowiki>''<nowiki>/>...<section end=</nowiki>''<nowiki>fragmentname</nowiki>''<nowiki>/></nowiki></code> tags and using {{pf|lst|''article''|''fragmentname''}} to transclude those fragments, which is equivalent to using the {{para|fragment|''fragmentname''}} parameter with this template. {{pf|lsth|''article''|''fragmentname''}} can also be used to transclude everything ''but'' those fragments.

The text will not be trimmed of excess whitespace, there will not be a header (equivalent to {{para|hat|no}}), and all files, templates, tables, references, and subsections will be included unless the source article is marked up with <code><nowiki><section begin=</nowiki>''<nowiki>fragmentname</nowiki>''<nowiki>/>...<section end=</nowiki>''<nowiki>fragmentname</nowiki>''<nowiki>/></nowiki></code>, {{tag|noinclude}}, or {{tag|onlyinclude}} tags. [[Help:Self link|Self links]] will appear in bold.

=== Citations ===

==== Differing styles ====

{{Further|Wikipedia:Citing sources#Variation in citation methods}}

It can happen that the source you want to excerpt contains footnotes in a [[WP:CITEVAR|different citation style]] than your article, and excerpting the source would cause a citation style mismatch, which is contrary to the guideline on [[Wikipedia:Citing sources|citing sources]]. Sometimes, excerpt can still be used, while avoiding a mismatch in style, by the use of params {{para|references|no}} and {{para|inline|yes}}.

If the source you want to excerpt has multiple ref-tags interspersed throughout the source, and they need to display exactly in those locations in order to maintain full [[WP:V|verifiability]], then this source might not be a good candidate for transclusion via the {{tl|excerpt}} template, and [[WP:CWW|copying the content]] from the source into the article might be a better choice. 

However, you can still use the Excerpt template, if the source page you want to excerpt meets '''either''' of these conditions: 
* references are found mostly or all at the end of the text to be excerpted; or 
* references are scattered throughout, but could legitimately be regrouped at the end of the excerpt without adversely affecting [[WP:V|verifiability]]. 
In either case, use params {{para|references|no}} to strip the ref-tags from the transcluded content, and {{para|inline|yes}} to define the excerpt as an [[HTML element#Inline elements|inline display element]] in order to {{slink||Suppress line breaks between paragraphs}}, and then manually append a copy of all the citations in the source immediately after the excerpt tag ending curly braces in the target article, with no intervening line breaks, white space, or other characters between the tag and the appended references. The copied references will have to be manually converted from [[Wikipedia:Citing sources#Short and full citations|short footnote-style to full, inline citation-style]], or vice-versa, to match the citation style of the target. '''Note:''' citations are not creative content, and [[Wikipedia:Copying within Wikipedia#Where attribution is not needed|attribution is not needed]] for copying them.

For an exception regarding the use of template {{t|R}} for the reuse of [[WP:NAMEDREFS|named references]], see {{slink||Incompatibilities}} below.

==== Another approach ====

It is advised to seek consensus before attempting this layout change.

If there are few shortened footnotes, a new subsection can be added to the "References" section to allow {{tl|sfn}} to link to the correct citations. Here is one approach, where the {{tl|sfn}} citations list in the excerpted article "SCBA" is titled "Works cited":

<syntaxhighlight lang="wikitext" highlight="7-8">
== Transcluded section ==
{{excerpt|SCBA}}

== References ==
{{reflist}}

=== From SCBA ===
{{excerpt|SCBA|Works cited|hat=0}}
</syntaxhighlight>

{{tl|sfn}} footnotes will now link to the citations created in the excerpted subsection.

==== Ref name collision ====

To prevent the possibility of collisions between [[WP:NAMEDREFS|named references]] in the transcluding and excerpted pages which would otherwise generate a [[Help:Cite errors/Cite error references duplicate key|duplicate key error]], all ref names in the excerpted content are altered by prefixing the name with the pagename of the excerpted page. Thus, if the ref on page {{kbd|MyArticle}} looks like <code><nowiki><ref name="Jones-2024"></nowiki></code>, then when excerpted by {{kbd|TargetPage}} it will be changed to <code><nowiki><ref name="MyArticle Jones-2024"></nowiki></code>, in order to avoid a collision with a possible "Jones-2024" ref already on the target page.

=== Excerpt trees ===

[[File:Excerpt tree.png|class=skin-invert-image|thumb|Visual representation of an imaginary excerpt tree.]]

When a very general article uses excerpts from more specific articles, which in turn use excerpts from even more specific articles, then a [[tree structure]] emerges, called an "Excerpt tree".

Here you can navigate the main excerpt trees on the English Wikipedia. It's useful for editors interested in expanding or improving them. To navigate the trees, click the following button<sup><abbr title="{{Int:gadgets-sister}}">(S)</abbr></sup>:

{{Clickable button|url={{fullurl:{{FULLPAGENAME}}#Excerpt trees|withJS=MediaWiki:ExcerptTree.js}} |2=See the excerpt trees}}

<div class="ExcerptTree" style="display: none;">

* [[January 6 United States Capitol attack]]
* [[Algae]]
* [[Africa]]
* [[Aquatic ecosystem]]
* [[Bangladesh]]
* [[Campanology]]
* [[Climate change in Africa]]
* [[Climate change in South Asia]]
* [[Climate justice]]
* [[COVID-19 pandemic]]
* [[Ecosystem]]
** [[Aquatic ecosystem]]
* [[Effects of climate change on humans]]
* [[Environmental impact of agriculture]]
* [[Eutrophication]]
* [[Fishing industry]]
* [[Food]]
* [[God]]
** [[Existence of God]]
* [[Hygiene]]
* [[List of carillons]]
* [[List of LGBT-related cases in the United States Supreme Court]]
* [[Marine debris]]
* [[Middle East]]
* [[Ocean]]
* [[Plastic pollution]]
* [[Public health]]
* [[Sanitation]]
* [[Sewage]]
* [[Sustainable Development Goals]]
* [[Tourism]]
* [[Wastewater treatment]]
* [[Water resources]]

</div>

=== Refinement using inclusion control ===

{{Further|Help:Template#Noinclude, includeonly, and onlyinclude}}

Sometimes, a passage will almost fit for a transclusion, but not quite. In these cases, you can edit the source page to add <code><nowiki><noinclude>...</noinclude></nowiki></code> tags around content you don't want in the excerpt and <code><nowiki><includeonly>...</includeonly></nowiki></code> tags around content you want only in the excerpt.

For instance, the page [[COVID-19 misinformation]] begins with "The [[COVID-19 pandemic]] has resulted in [[misinformation]]...". However, when excerpting this lead to the misinformation section of [[COVID-19 pandemic]], we don't need to specify which pandemic we're referring to. Therefore, the code <code><nowiki>The <noinclude>[[COVID-19 pandemic]]</noinclude><includeonly>pandemic</includeonly> has resulted in [[misinformation]]</nowiki></code> can be used at the misinformation page, so that it will appear at the pandemic page as "The pandemic has resulted in [[misinformation]]...".

For pages with a high volume of edits, it may be a good idea to leave a hidden comment explaining why the tags are there, so that no one will be [[WP:FENCE|tempted]] to remove them, like so: <code><nowiki>The <noinclude>[[COVID-19 pandemic]]</noinclude><!--These tags are used to refine the excerpt at [[COVID-19 pandemic]]--><includeonly>pandemic</includeonly> has resulted in [[misinformation]]</nowiki></code>

Please note that when the <code><nowiki></noinclude></nowiki></code> tag is wrapped into a new line, a character next to it would be interpreted as a line beginning. This can lead to some formatting problems. For example, when a <code><nowiki></noinclude></nowiki></code> at line beginning is succeeded by a [[whitespace character]], the page engine would translate this as a [[Help:Wikitext#Limiting formatting / escaping wiki markup|leading space]] that renders the subsequent paragraph in [[code block]] and [[monospaced font]] with preserved formatting. For this reason, no spaces should separate the <code><nowiki></noinclude></nowiki></code> tag from the text it precedes.

=== Replacing summary section with excerpt of child article ===

[[File:How to excerpt.webm|thumb|How to replace a section with an excerpt.]]

A section is often a [[WP:Summary style|summary]] in a [[WP:G#Parent article|parent article]] of a more detailed page about a subtopic located in a [[WP:G#child page|child page]]; these are generally linked with [[Template:Main]] in the parent. Sometimes it's convenient to replace the content of such a summary section in the parent with an excerpt of the child page lead (after merging any valuable content of the section into the child page). In such cases, an efficient way to proceed is:

# Open the parent section for editing in one tab, and the child article in another.
# Copy the text of the parent section and append it to the lead section of the child page.
# Consolidate and adjust the combined lead using common sense.
# Save the changes in the child article with an [[WP:ES|edit summary]] like: "{{xt|<nowiki>Copied content from [[Page]]. See that article's history for attribution."</nowiki>}}
# Back in the parent page section, delete all content except the section header and replace it with an excerpt of the child page.
# Save the changes in the section; proposed edit summary: "{{xt|Moved section content to <nowiki>[[Child page title]]</nowiki> and replaced with excerpt.}}"

'''IMPORTANT!''' In step four, include the '''full''' edit summary as shown to comply with Wikipedia's [[Wikipedia:Copying within Wikipedia|copyright policy]]. If you forget to do this at the time of the original edit, follow the instructions on [[Wikipedia:Copying within Wikipedia#Repairing insufficient attribution|Repairing insufficient attribution]] to create a dummy edit with the required edit summary.

=== Suppress line breaks between paragraphs ===

If you want to merge two excerpted paragraphs from a source into one longer one in your article, use two excerpts instead of one, and change the display mode to [[HTML element#Inline elements|inline]]. So, for example, instead of this :
: {{tlc|excerpt|Ocean color|paragraphs{{=}}2-3|file{{=}}no}} // (example taken from [[Ocean#Color]])
you could code:
: {{tlc|excerpt|Ocean color|paragraphs{{=}}2|file{{=}}no|inline{{=}}yes}}
: {{tlc|excerpt|Ocean color|paragraphs{{=}}3|file{{=}}no|inline{{=}}yes}}
and this will remove the [[Help:Line-break handling#Newlines|line break]] between the two paragraphs, so they will render as one paragraph.

By default, an {{tl|excerpt}} generates an HTML [[div and span#Differences and default behaviour|div-tag]], which is a [[HTML element#Block elements|block-level display element]], so contiguous excerpts are normally separate block elements with line breaks between them. This can be overridden through use of param {{para|inline|yes}}, which suppresses the div-tag, and results in an [[HTML element#Inline elements|inline display element]] instead. In this case, just as with running text on adjacent lines of [[wikicode]], no line break is generated between them.
This technique can also be adapted to [[#Differing citation styles|§&nbsp;change citation style]] or use different references.

=== Mitigating side effects of unexpected source file changes ===

{{anchor|HIDDENEXCERPTADVICE}}{{tsh|TM:HIDDENEXCERPTADVICE}}

Excerpting content from a source page section into a target may cause [[WP:Link|link rot]] and other undesirable effects in the target if the heading or source content changes unexpectedly. Editors of the source page are generally unaware that editing the source can have side effects elsewhere. This situation can be mitigated by adding a [[WP:Hidden|hidden text]] message at the source page section being excerpted:
: <code><nowiki><!-- Note: Content in this section is {{excerpt}}ed by "PageName#SectionName". See TM:HIDDENEXCERPTADVICE. --></nowiki></code>
This alerts editors of the source file that part or all of the content in the area below the message is excerpted onto another page, so the editor can take target page side effects into account during their edit. Changing the heading is analogous to [[MOS:HIDDENLINKADVICE]], which describes how to avoid undesirable side effects when a section heading change may lead to a  broken redirect.

'''What to do'''

If you are about to edit a section that contains a hidden excerpt advice message, what should you do? 

* If your prospective changes are typos, grammar, or wording adjustments '''without changing the section heading''', most likely you don't need to do anything
* If you are changing the section heading, then this will likely break the {{t|excerpt}} and leave an error message at the target page. Have a look at the indicated source page and find the {{t|excerpt}} template. If it contains a pointer to the old section heading name on the source page section (see [[Template:Excerpt#Parameters|positional parameter 2]]), then you should update that parameter to the new section name.
* If you are making a substantial change to excerpted content at the source in a way that may adversely affect the target page, you could:
*# raise a discussion at the target Talk page, to advise editors about changes to the source; you could link [[TM:HIDDENEXCERPTADVICE]] in the discussion or in the edit summary 
*# replace the {{t|excerpt}} template in the target with content [[WP:CWW|copied]] from the version of the source before you changed it. (Don't forget to provide [[WP:CWW|copy attribution]] in the edit summary). This is a permanent solution for that excerpt, and you should remove the hidden link from the source page after completing it.

== Advantages and disadvantages ==

The use of {{tl|Excerpt}} has the following advantages:

* '''Reduces maintenance''' by avoiding duplicate content that must be updated multiple times
* '''Improves content quality''' by encouraging editors to merge related content, rather than having multiple versions in various stages of development (see [[#Replacing summary section with excerpt of child article]])
* '''Fosters collaboration''' by channeling contributors into one place, rather than working in parallel
* '''Promotes rapid development''' of articles, especially those written in [[WP:Summary style|summary style]]

It also has the following disadvantages:

* '''Verification concerns''' as an excerpt may have [[Wikipedia:Verifiability|no sources]] for statements that should be [[WP:BURDEN|sourced where they appear]],  have different [[WP:CITEVAR|established reference styles]],  contain [[Help:Cite errors/Cite error references no text|no-text cite errors]], or [[Help:Cite errors/Cite error references duplicate key|duplicate key errors]]
* '''Impediment to editing''' as you have to go to the sub article to make changes to the main article (though excerpts include a hatnote with an [edit] button to edit the excerpted article in one click)
* '''Reduces accuracy''' as an excerpt of one article is not always a perfect fit into a new article (but see [[#Refinement using inclusion control]])
* '''Decreases visibility''' as changes to the sub article will not appear on the watchlist of editors of the main article (see [[phab:T55525]])
* '''Risk of linkrot''' as pages or sections are blanked, moved, or deleted; this may result in the appearance of [[#Error messages|§&nbsp;error messages]] on the page (but see {{slink||Mitigating side effects of unexpected source file changes}} above; additionally, broken excerpts are automatically tracked at [[:Category:Articles with broken excerpts]] and regularly fixed).

{{See|Help:Transclusion#Drawbacks}}

==Incompatibilities==

{{Replace | {{excerpt|Template:R/doc|Incompatibilities |hat=no}} | this template | template {{tl|R}} }}

To work around this, you may exclude the R template from the excerpt using param 'template' with the minus sign ({{para|template|-r}}) and then manually tack on a citation using a standard ref-tag after the the excerpt to reinsert the excluded citation. Please also use {{para|inline|yes}} to ensure no blank space or newline between the excerpted content and your ref tag.

For example, you could do this to transclude the first paragraph of [[Doug Flutie#New Jersey Generals]], which employs {{tlx|r|nfl20141017}} to reuse a named citation:
: <code><nowiki>{{excerpt|Doug Flutie|New Jersey Generals|only=paragraph|template=-r|inline=yes}}<ref name="nfl20141017">{{cite episode |title=Doug Flutie |series=A Football Life |network=NFL Network |airdate=October 17, 2014}}</ref></nowiki></code>
with the reference tacked on at the end to replace the excluded R template. <span class=plainlinks>([https://en.wikipedia.org/w/index.php?title=Special:ExpandTemplates&wpContextTitle=&wpInput=%7B%7Bexcerpt%20%7CDoug%20Flutie%20%7CNew%20Jersey%20Generals%20%7Conly%3Dparagraph%20%7Ctemplate%3D-r%20%7Cinline%3Dyes%7D%7D%3Cref%20name%3D%22nfl20141017%22%3E%7B%7Bcite%20episode%20%7Ctitle%3DDoug%20Flutie%20%7Cseries%3DA%20Football%20Life%20%7Cnetwork%3DNFL%20Network%20%7Cairdate%3DOctober%2017%2C%202014%7D%7D%3C%2Fref%3E%0A%0A%7B%7Breflist-talk%7D%7D Show me!])</span>

== Error messages ==

If an error is detected, an error message will appear in the article in place of the expected transcluded content:

* <span class="error">No page given</span> – No page was passed to the template <!--error-no-page-->
* <span class="error">Title X is not valid</span> – The title passed is not valid (contains [[Wikipedia:Naming conventions (technical restrictions)#Forbidden characters|forbidden characters]] such as < or >) <!--error-invalid-title-->
* <span class="error">Page X not found</span> – The page passed does not exist, or the page is a redirect and the target page was not found <!--error-page-not-found-->
* <span class="error">Lead section is empty</span> – The page exists, but cannot excerpt from non-existent lead <!--error-lead-empty-->
* <span class="error">Section X not found</span> – The page exists, but cannot excerpt the desired section because either:
** The given section does not exist. <!--error-section-not-found--> This may occur if the source page section is removed or renamed. To help mitigate this, see [[MOS:BROKENSECTIONLINKS]].
** The given section exists, but is excluded from transclusion by one of the [[Help:Template#Inclusion control: noinclude, includeonly, and onlyinclude|inclusion control]] tags. 
* <span class="error">Section X is empty</span> – The given section exists, but is empty <!--error-section-empty-->
* <span class="error">Template loop detected</span> – The excerpted section contains itself an excerpt. While this is not strictly a template loop, the software considers it so. To fix it, skip the intermediate excerpt ([[Special:Diff/1184292340|example]]).

== See also ==

* [[Module:Excerpt]]
* [[Module:Excerpt/config]]
* [[Module:WikitextParser]]
* [[c:Data:I18n/Module:Excerpt.tab]]
* [[Help:Transclusion#Drawbacks]]
* [[:Category:Articles with excerpts]], or [https://en.wikipedia.org/w/index.php?title=Special%3AWhatLinksHere&target=Template%3AExcerpt&namespace=0 Articles that link to "Template:Excerpt"] (unsorted)
* [[:Category:Articles with broken excerpts]]
* [[Help:Labeled section transclusion]] – A more efficient method for simple section transclusions
* [[Wikipedia:Transclusion#Selective transclusion]] – How to transclude one or more sections of an article or project page into another
* [[Wikipedia:Summary style#Synchronization]]
* [[Wikipedia:Manual of Style/Lead section]]
* [[Wikipedia:WikiProject Introductions]]
* {{tl|Transclude lead excerpt}} and {{tl|Transclude linked excerpt}} – Templates designed for excerpt transclusion in portals
* {{tl|Transcluded section}} – Creates hatnote but ''does not transclude'' the section
** [https://en.wikipedia.org/w/index.php?title=Special%3AWhatLinksHere&target=Template%3ATranscluded+section&namespace=0 Pages that link to "Template:Transcluded section" (articles)] (unsorted)
* {{tl|Transcluding article}} – Transcludes one or more entire pages
** [https://en.wikipedia.org/w/index.php?title=Special%3AWhatLinksHere&target=Template%3ATranscluding+article&namespace=0 Pages that link to "Template:Transcluding article" (articles)] (unsorted)
* {{tl|Template parameter value}} – Extracts the value of a parameter passed to a template
* [[meta:Grants:Project/Rapid/Sophivorus/Excerpts]] - Grant to spread excerpts to various Wikipedias
* [[meta:Concise Wikipedia]] - Perennial new project proposal (see the [[meta:Concise Wikipedia#A summary of existing short-options, using an example|comparison table]] at the bottom in particular)
* [[Single source of truth]]
* [[Wikimania:2021:Submissions/Excerpts: Modular and Reusable Content within Wikipedia|Excerpts: Modular and Reusable Content within Wikipedia]] - Video presentation about excerpts for Wikimania 2021

== Template data ==

<templatedata>
{
	"params": {
		"1": {
			"aliases": [
				"article",
				"page"
			],
			"label": "Article",
			"description": "Name of the article or page to transclude",
			"example": "Science",
			"type": "wiki-page-name",
			"required": true
		},
		"2": {
			"aliases": [
				"section",
				"fragment"
			],
			"label": "Section",
			"description": "Name of the section or <section> tag to transclude",
			"example": "History",
			"type": "string"
		},
		"paragraphs": {
			"label": "Paragraphs",
			"description": "Paragraphs to transclude",
			"example": "1-3,5",
			"type": "string",
			"aliases": [
				"paragraph"
			]
		},
		"files": {
			"label": "Files",
			"description": "Files to transclude",
			"example": "1-3,5",
			"type": "string",
			"default": "1",
			"aliases": [
				"file"
			]
		},
		"subsections": {
			"label": "Subsections",
			"description": "Whether to transclude the subsections of the requested section",
			"example": "yes",
			"type": "boolean"
		},
		"tables": {
			"label": "Tables",
			"description": "Tables to transclude",
			"example": "Stats2020",
			"type": "string",
			"aliases": [
				"table"
			]
		},
		"references": {
			"label": "References",
			"description": "Whether to transclude the references",
			"example": "no",
			"type": "boolean"
		},
		"only": {
			"label": "Only",
			"description": "Transclude only this kind of element",
			"example": "table",
			"type": "string"
		},
		"this": {
			"label": "This",
			"description": "Change the initial text of the hatnote",
			"example": "This gallery is",
			"type": "string"
		},
		"displaytitle": {
			"label": "Display title",
			"description": "Change the text of the link in the hatnote",
			"type": "string"
		},
		"class": {
			"label": "Class",
			"description": "Additional CSS class",
			"example": "noprint",
			"type": "string"
		},
		"hat": {
			"label": "Hatnote",
			"description": "Whether to include the hatnote",
			"example": "no",
			"type": "boolean",
			"default": "yes"
		},
		"bold": {
			"label": "Bold",
			"description": "Whether to preserve bold text",
			"example": "no",
			"type": "boolean",
			"default": "yes"
		},
		"links": {
			"label": "Wikilinks",
			"description": "Whether to preserve wikilinks",
			"example": "no",
			"type": "boolean",
			"default": "yes"
		},
		"quote": {
			"label": "Quote",
			"description": "Wraps the excerpt in <blockquote> tags",
			"example": "yes",
			"type": "boolean",
			"default": "no"
		},
		"inline": {
			"label": "Inline",
			"description": "Remove the hatnote and <div> tags around the excerpt, to use it inside other text",
			"example": "yes",
			"type": "boolean",
			"default": "no"
		},
		"lists": {
			"aliases": [
				"list"
			],
			"label": "Lists",
			"description": "Lists to transclude",
			"example": "1",
			"type": "string"
		},
		"templates": {
			"aliases": [
				"template"
			],
			"label": "Templates",
			"description": "Templates to transclude",
			"example": "Infobox person",
			"type": "string"
		},
		"onlyfreefiles": {
			"label": "Only free files",
			"description": "Disable transclusion of non-free files",
			"example": "no",
			"type": "boolean",
			"default": "yes"
		},
		"briefdates": {
			"label": "Brief dates",
			"description": "Abbreviate birth and death information to (YYYY-YYYY) format",
			"example": "yes",
			"type": "boolean",
			"default": "no"
		}
	},
	"description": "This template is used for transcluding part of an article into another article.",
	"paramOrder": [
		"1",
		"2",
		"only",
		"paragraphs",
		"files",
		"tables",
		"lists",
		"templates",
		"references",
		"subsections",
		"hat",
		"bold",
		"links",
		"quote",
		"this",
		"displaytitle",
		"inline",
		"onlyfreefiles",
		"briefdates",
		"class"
	]
}
</templatedata>

<includeonly>{{sandbox other||
<!-- Categories go below this line; interwikis go to Wikidata. -->
[[Category:Wikipedia page-section templates]]
[[Category:Transclude page content templates]]
}}</includeonly>