Spaces rather than tabs.  Listing the entries now works, giving as many
characters as can fit on the screen of the first line.  Does not yet
support pasting from a specific line or limiting the list.
Don't need to specify if the function was specified; just shift the
argument list and check if the operation was set.
This will make the argument parsing slightly easier I hope.  Make sure
that the operation is specified, then invoke it using a function naming
convention and some metaprogramming.