is a JSON path string literal, written according to the rules given in

<xref linkend="datatype-jsonpath"/>. This means in particular that any

backslashes you want to use in the regular expression must be doubled.

For example, to match strings that contain only digits:

For example, to match string values of the root document that contain

only digits:

<programlisting>

$ ? (@ like_regex "^\\d+$")

$.* ? (@ like_regex "^\\d+$")

</programlisting>

</para>

</sect3>