Multi-line C comments

Built from a regular expression

// built from regexp /\*/*(([^*/][^*]*)?\*+)*/

star matches {event:'func_pre',name:'star'};
slash matches {event:'func_pre',name:'slash'};
other matches {event:'func_pre',name:'other'};

not_star_slash matches other;
not_star matches slash | other;

Main=slash star slash* ((not_star_slash not_star*)?star+)* slash;

Built from a DFA

// built from  a DFA 

star matches {event:'func_pre',name:'star'};
slash matches {event:'func_pre',name:'slash'};
other matches {event:'func_pre',name:'other'};

not_star_slash matches other;
not_star matches slash | other;

Main=slash star Inner;
Inner=not_star Inner \/ star MayStop;
MayStop=slash \/ star MayStop \/ not_star_slash Inner;

ReDoS

a matches {event:'func_pre',name:'a'};
b matches {event:'func_pre',name:'b'};

Main = (a+)+;