Editing Help:Template (section)

===Problems and workarounds===
* The following techniques are helpful in debugging a template:
** Use [[Special:ExpandTemplates]] to see the full recursive expansion of one or more templates.
** Use <code>subst:</code> to substitute a template (rather than transclude it), which can show more clearly what is happening when the template is transcluded; see [[Help:Substitution]].
** Use <code>msgnw:</code> (short for "'''m'''e'''s'''sa'''g'''e, '''n'''o'''w'''iki") to more-or-less transclude the source of the template rather than its expansion. It is not perfect: lists are rendered, comments are removed, and single newlines are replaced with spaces (which is particularly confounding when transcluding wikitext tables).
* If the first character of a template expansion (or parser function result) is one of four wiki markup characters—<code>:</code>, <code>;</code>, <code>*</code>, <code>#</code>{{efn|These are defined in the [https://web.archive.org/web/20180625163321/https://doc.wikimedia.org/mediawiki-core/master/php/classParser.html#ad463888e40c078ac9bcfcaf1231e39d7 <code>doBlockLevels</code> function of Parser.php].}}, it is processed during display as though it were at the beginning of a line, even if the template call is not. This allows you to create various kinds of lists with templates where the template call may not be in the correct place for a list. To avoid this, use {{xtag|nowiki|s}} before the markup or {{tag|nowiki}} around it, or use the [[HTML]] entities <code>&amp;#58;</code>, <code>&amp;#59;</code>, <code>&amp;#42;</code>, <code>&amp;#35;</code>, or use the templates {{tl|colon}}, {{tl|;}}, {{tl|asterisk}}, {{tl|number sign}} (those templates may not exist at other wikis). In some cases, the HTML entities will work when the {{tag|nowiki|s}} does not. The problem often occurs when a parameter value in a template call starts with one of the four characters. See also {{tl|Encodefirst}}. 
* For issues with template substitution, such as how to control whether subtemplates are substituted as well when the parent template is substituted, see [[Help:Substitution]].
* You can use the template {{tlx|Trim}} to strip any initial or final whitespace from unnamed parameter values if this would cause problems; <em>named</em> parameter values are automatically stripped in this way.
* To protect server resources and avoid infinite loops, the parser imposes certain limits on the depth of transclusion nesting and on the page size with expanded templates. This may cause a page to break if it uses very complex templates, particularly if there are multiple such templates on the same page. For more information, see [[WP:Template limits]]. You can check a page's overall load on the server by examining the generated HTML for a page and looking for the <code>NewPP limit report</code> comments.
* Do not use <code>=</code> wikimarkup to create a section header in a template which is intended for use in article space; this will create an edit link on a page that transcludes the template that will confusingly open the <em>template</em> for editing.
* You may avoid section edit links to the template by including <code><nowiki><includeonly>__NOEDITSECTION__</includeonly></nowiki></code>.