Major feature enhancements, Minor bugfixes, Stable
Unicode version 6.0 is now supported. Regular expressions can now be reset to the default modifiers. Four new regular expression modifiers, "/d", "/l" , "/u", and "/a", were introduced. The substitution operators now support the modifier "/r" to work non-destructively, leaving the original unmodified. Larger octals can now be specified. Array and hash operators can now experimentally operate directly on hard references. printf-like functions now understand post-1980 size modifiers. Exception handling was made more reliable and consistent. Other enhancements and many bug fixes were made.