http://www.perlmonks.org?node_id=640509


in reply to Re^5: Yet Another Rosetta Code Problem (Perl, Ruby, Python, Haskell, ...) (js)
in thread Yet Another Rosetta Code Problem (Perl, Ruby, Python, Haskell, ...)

Telling m//g in list context to forget about the captures and just return the matches:

@list = "ZBBCZZ" =~ /(??{'(.)\1*'})/g;

or probably more exact: there are no captures m// can see