This template is a metatemplate. It is used to build other templates and should not be used standalone, except for testing or simple usage.
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This is a metatemplate that can be wrapped around a template that requires substitution. It should always be safe-substituted (e.g. {{safesubst:require subst}}).

<includeonly>{{safesubst:require subst|template= [Name of template] |1=</includeonly>
... (normal template code) ...
<includeonly>}}</includeonly>

If a substituted template is transcluded instead of substituted, an error message is displayed. For example:

This template must be substituted. Replace {{template name ...}} with {{subst:template name ...}}.