<title>ICU Collation Settings</title>
      <tgroup cols="4">
       <colspec colname="col1" colwidth="1*"/>
       <colspec colname="col2" colwidth="2*"/>
       <colspec colname="col3" colwidth="2*"/>
       <colspec colname="col4" colwidth="5*"/>

       <thead>
        <row>
         <entry>Key</entry>
         <entry>Values</entry>
         <entry>Default</entry>
         <entry>Description</entry>
        </row>
       </thead>

       <tbody>
        <row>
         <entry><literal>co</literal></entry>
         <entry><literal>emoji</literal>, <literal>phonebk</literal>, <literal>standard</literal>, <replaceable>...</replaceable></entry>
         <entry><literal>standard</literal></entry>
         <entry>
          Collation type. See <xref linkend="icu-external-references"/> for additional options and details.
         </entry>
        </row>

        <row>
         <entry><literal>ka</literal></entry>
         <entry><literal>noignore</literal>, <literal>shifted</literal></entry>
         <entry><literal>noignore</literal></entry>
         <entry>
          If set to <literal>shifted</literal>, causes some characters
          (e.g. punctuation or space) to be ignored in comparison. Key
          <literal>ks</literal> must be set to <literal>level3</literal> or
          lower to take effect. Set key <literal>kv</literal> to control which
          character classes are ignored.
         </entry>
        </row>

        <row>
         <entry><literal>kb</literal></entry>
         <entry><literal>true</literal>, <literal>false</literal></entry>
         <entry><literal>false</literal></entry>
         <entry>
          Backwards comparison for the level 2 differences. For example,
          locale <literal>und-u-kb</literal> sorts <literal>'àe'</literal>
          before <literal>'aé'</literal>.
         </entry>
        </row>

        <row>
         <entry><literal>kc</literal></entry>
         <entry><literal>true</literal>, <literal>false</literal></entry>
         <entry><literal>false</literal></entry>
         <entry>
          <para>
           Separates case into a "level 2.5" that falls between accents and
           other level 3 features.
          </para>
          <para>
           If set to <literal>true</literal> and <literal>ks</literal> is set
           to <literal>level1</literal>, will ignore accents but take case
           into account.
          </para>
         </entry>
        </row>

        <row>
         <entry><literal>kf</literal></entry>
         <entry>
          <literal>upper</literal>, <literal>lower</literal>,
          <literal>false</literal>
         </entry>
         <entry><literal>false</literal></entry>
         <entry>
          If set to <literal>upper</literal>, upper case sorts before lower
          case. If set to <literal>lower</literal>, lower case sorts before
          upper case. If set to <literal>false</literal>, the sort depends on
          the rules of the locale.
         </entry>
        </row>

        <row>
         <entry><literal>kn</literal></entry>
         <entry><literal>true</literal>, <literal>false</literal></entry>
         <entry><literal>false</literal></entry>
         <entry>
          If set to <literal>true</literal>, numbers within a string are
          treated as a single numeric value rather than a sequence of
          digits. For example, <literal>'id-45'</literal> sorts before
          <literal>'id-123'</literal>.
         </entry>
        </row>

        <row>
         <entry><literal>kk</literal></entry>
         <entry><literal>true</literal>, <literal>false</literal></entry>
         <entry><literal>false</literal></entry>
         <entry>
          <para>
           Enable full normalization; may affect performance. Basic
           normalization is performed even when set to
           <literal>false</literal>. Locales for languages that require full
           normalization typically enable it by default.
          </para>