From @AlexDaniel

Code​:
.say for combinations -999999999999999999, 2

Result​:
(no output)

� That's fine!

Code​:
.say for combinations -9999999999999999999, 2

Result​:
(0 1)
(0 2)
(0 3)
(0 4)
(0 5)
� and so on�

� now that's a problem.

From @usev6

This works consistently now​:

$ perl6-m -e '.say for combinations -9999999999999999999, 2'
()

$ perl6-m -e '.say for combinations -999999999999999999, 2'
()

Calling combinations with a negative $k gives an empty list​:

$ perl6-m -e 'say combinations 4, -2'
()

I added tests for this behaviour to S32-list/combinations.t with commit Raku/roast@132d97ffc9

I'm closing this ticket as 'resolved'.

@usev6 - Status changed from 'new' to 'resolved'