If the syntax bit
RE_LIMITED_OPS is set, then Regex doesn't recognize
this operator. Otherwise, if the syntax bit
set, then ‘+’ represents this operator; if it is, then ‘\+’
This operator is similar to the match-zero-or-more operator except that it repeats the preceding regular expression at least once; see Match-zero-or-more Operator, for what it operates on, how some syntax bits affect it, and how Regex backtracks to match it.
For example, supposing that ‘+’ represents the match-one-or-more operator; then ‘ca+r’ matches, e.g., ‘car’ and ‘caaaar’, but not ‘cr’.