tern can match only at end of subject
  PCRE2_NOTBOL            Subject string is not the beginning of a line
  PCRE2_NOTEOL            Subject string is not the end of a line
  PCRE2_NOTEMPTY          An empty string is not a valid match
  PCRE2_NOTEMPTY_ATSTART  An empty string at the start of the subject is not a valid match
  PCRE2_NO_JIT            Do not use JIT matching
  PCRE2_NO_UTF_CHECK      Do not check the subject for UTF validity (only relevant if PCRE2_UTF
                           was set a