5.002 (prototypes)
5.6 (threads, UTF-8, our)
5.8 (64 bit, PerlIO default, ithreads)
5.10 (defined-or, recursive regex & named capture, smart match)
5.12 (package NAME VERSION, ... operator, pluggable keywords)
5.14 (regex improvements e.g. new modifiers and reentrancy, push etc on $aryref)
5.16 (CORE::, __SUB__, unicode_eval & evalbytes)
5.18 (hash randomization, lexical subs, regex set)
5.20 (sub signatures, new slice syntax, post deref)
5.22 (double diamond, bitwise operators, aliasing by reference)
5.24 (postfix deref no longer experimental, ordered arguments in sprintf, \b{lb} in regex)
5.26 (lexical subs no longer experimental, "." removed from @INC, indented heredocs)
5.28 (delete on key/value hash slices, safer perl -i, alphabetic synonyms on some regex assertions)
5.30 (variable-length lookbehind, wildcard in unicode property)
5.32 (isa operator, chained comparison, perl is now on github)
5.34 (try/catch, octal syntax 0o777)
5.36 (iterating multiple values in for(), sub signatures no longer experimental, builtin::*)
5.38 (Corinna?)