Nope, you can't use pop, unless you use it like this: "@{[pop]}" .. The quotes turn it into a string instead of an integer, so the | does a bitstring or instead of a numeric or. If either of the operands are numeric, you'll get the numeric or:

perl -we 'print "000"|1'
1
[download]

that doesn't work for us, we need this:

perl -we 'print "000"|"1"'
100
[download]

--sean

and yeah, i came up with a handful of slightly different attempts that all came in at 55 too.