(Hope this is the right spot for this!)
Pythonists complain that Perl doesn't have an interactive mode, but of course you can easily make one. However other examples I have seen were 20 line scripts, a little while ago I made up this one liner (which I tend to stash in a minimal shell script called ip, on every machine I use):
perl -ne 'print join(",", eval),"\n> "'
(Of course half that is just for prettification, if you don't mind ugly you can just say perl -ne 'print eval'
.) It does pretty much everything you hope (provided your shell handles up arrow history for you). An example session:
> $a *= 3
> sprintf '%lx', ~$a
> use Digest::SHA 'sha256_hex'
> sha256_hex 10
Although also very useful for testing small confusions about syntax, I've found it so handy as a sort of super calculator that I now keep an instance running all the time.