</varlistentry>
<varlistentry>
+ <term><literal>-=</literal></term>
+ <listitem>
+ <para>Remove the value from a key that holds a list of entries.</para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><literal>:=</literal></term>
<listitem>
<para>Assign a value to a key finally; disallow any later changes.</para>