For some reason htp.p successfully prints only within 30000 characters substring limit. And I would like to rewrite the following code in a smarter, beautified, eloquent manner:

declare
   p_clob clob;
   p_clob1 clob;
   p_clob2 clob;
   p_clob3 clob;
begin
   p_clob := my_pkg.render(arg_one => :P100_ITEM); -- my_pkg.render returns a CLOB with HTML
   p_clob1 := substr(p_clob,0,30000);
   p_clob2 := substr(p_clob,30001,60000);
   htp.p(p_clob1);
   htp.p(p_clob2);
exception when others then
   htp.p(length(p_clob));
end;

Facultative question

What's htp.p, what limitations does it have and why it is not listed in this documentation?