[#boost-urls-grammar-delim_rule-01] = xref:boost/urls/grammar/delim_rule-01.adoc[boost::urls::grammar::delim_rule] :relfileprefix: ../../../ :mrdocs: Match a single character from a character set == Synopsis Declared in `<https://www.github.com/boostorg/url/blob/develop/include/boost/url/grammar/delim_rule.hpp#L157[boost/url/grammar/delim_rule.hpp]>` [source,cpp,subs="verbatim,replacements,macros,-callouts"] ---- template<xref:boost/urls/grammar/CharSet.adoc[CharSet] CS> constexpr /* implementation-defined */ delim_rule(CS const& cs) noexcept requires ! std::is_convertible< CS, char>::value; ---- == Description This matches exactly one character which belongs to the specified character set. The value is a reference to the character in the underlying buffer, expressed as a `core::string_view`. The function xref:boost/urls/grammar/squelch.adoc[`squelch`] may be used to turn this into `void` instead. If there is no more input, the error code xref:boost/urls/grammar/error.adoc[`error::need_more`] is returned. == Value Type [,cpp] ---- using value_type = core::string_view; ---- == Example Rules are used with the function xref:boost/urls/grammar/parse-09.adoc[`parse`]. [,cpp] ---- system::result< core::string_view > rv = parse( "X", delim_rule( alpha_chars ) ); ---- == Return Value A rule which matches a single character from the set. == Parameters [cols=2] |=== | Name | Description | *cs* | The character set to use. |=== == See Also xref:boost/urls/grammar/alpha_chars.adoc[`alpha_chars`], xref:boost/urls/grammar/parse-09.adoc[`parse`], xref:boost/urls/grammar/squelch.adoc[`squelch`]. [.small]#Created with https://www.mrdocs.com[MrDocs]#