pv: docs for xavp_params_implode(...) function

src/modules/pv/doc/pv_admin.xml

@@ -292,6 +292,37 @@ xavp_params_explode("a=b;c=d;e=d", "x");
 #    $xavp(x=>a) = "b";
 #    $xavp(x=>c) = "d";
 #    $xavp(x=>e) = "f";
+...
+				</programlisting>
+			</example>
+		</section>
+		<section id="pv.f.xavp_params_implode">
+			<title>
+				<function moreinfo="none">xavp_params_implode(xname, pvname)</function>
+			</title>
+			<para>
+				Serialize the subfields in an XAVP to a parameters string format.
+			</para>
+			<para>
+				The first parameter has to be the name of XAVP (only the string
+				name, not the in $xavp(name)). The second parameter
+				is the name of output variable (in full name, like $var(output)).
+			</para>
+			<para>
+				The value is stored as string type.
+			</para>
+			<para>
+			Function can be used from ANY ROUTE.
+			</para>
+			<example>
+				<title><function>xavp_params_implode</function> usage</title>
+				<programlisting format="linespecific">
+...
+$xavp(x=&gt;e) = "f";
+$xavp(x[0]=&gt;c) = "d";
+$xavp(x[0]=&gt;a) = "b";
+xavp_params_implode("x", "$var(out)");
+# results in: $var(out) is "a=b;c=d;e=f;"
 ...
 				</programlisting>
 			</example>