Documentation for constant Empty assembled from the following pages:

Class: Slip §

From Slip

(Slip) constant Empty §

Empty is a Slip of the empty List.

say "".comb ~~ Empty;
# OUTPUT: «True␤»

For example, these constructs with a failing test return Empty:

do if 0 {};
(42 if 0);
do with Any {};
(42 with Any);