From zefram@fysh.org

doc/doc/Type/Slip.pod says​:

  =head2 sub slip

  sub slip(*@​) returns Slip​:D

  Creates a L<Slip|/type/Slip> from its arguments.

rakudo/src/core/Slip.pm has​:

  multi slip(+args) { args.Slip }

Is the slurpy parameter meant to be of flattening or one-arg form?
This makes a difference in cases such as slip(11,[22,33]). (To my mind
it should be of slicing form, on least-surprise grounds. Either kind of
flattening is liable to be a surprise, as demonstrated by [perl #​126902].)

-zefram