  We introduce a new technique for constructing a finite state deterministic
automaton from a regular expression, based on the idea of marking a suitable
set of positions inside the expression, intuitively representing the possible
points reached after the processing of an initial prefix of the input string.
Pointed regular expressions join the elegance and the symbolic appealingness of
Brzozowski's derivatives, with the effectiveness of McNaughton and Yamada's
labelling technique, essentially combining the best of the two approaches.
