<pre>
  cat(er(pillar)?)?
</pre>
is matched against the string "the caterpillar catchment", the result is the
three strings "caterpillar", "cater", and "cat" that start at the fifth
character of the subject. The algorithm does not automatically move on to find
matches that start at later positions.
</P>
<P>
PCRE2's "auto-possessification" optimization usually applies to character
repeats at the end of a pattern (as well as internally). For example, the
pattern "a\d+" is compiled as if it were "a\d++" becaus