In Routine§
See primary documentation in context for trait is raw.
multi trait_mod:<is>(Routine:D $r, :$raw!)
Gives total access to the data structure returned by the routine.
my @zipi = <zape zapatilla>; sub þor() is raw { return @zipi }; þor()[1] = 'pantuflo'; say @zipi; # OUTPUT: «[zape pantuflo]»