$item = 0x37;  # ...or 00110111b

##</code><code>##

$ perl -le 'print vec(0x37, $_, 1) for 0..7'        # Ooops!!!
$ perl -le 'print vec(chr(\x37), $_, 1) for 0..7'   # Much better. 
$ perl -le 'print vec("\x37", $_, 1) for 0..7'      # This works too.

##</code><code>##

   
$ perl -le 'print for map chr, unpack "c*", unpack "b*", chr(0x37)'