parse source a
say "parse source: ["a"]"
say

say "number of" arg() "arguments that are valid:"
do x=1 to arg()
    val=arg(x)
    say " arg #" x": ["val"]"
    if val~isA(.directory) then
    do
        say "these arguments can be seen in the following directory:"
        loop idx over val~allIndexes~sort
            say " idx=["idx"] -> item=["val[idx"]"]
        end
    end
end