Sedsed v1.1 and earlier does not support the ~ and + GNU sed extensions for addresses:
$ ./sedsed.py -e '1~2p'
ERROR: invalid SED command '~' at line 1
$ ./sedsed.py -e '1,~2p'
ERROR: invalid SED command '~' at line 1
$ ./sedsed.py -e '1,+2p'
ERROR: invalid SED command '+' at line 1
$
Sedsed v1.1 and earlier does not support the
~
and+
GNU sed extensions for addresses: