4.3BSD/usr/contrib/icon/test/distr/std01.out

c := 'abcd' ----> 'abcd'
c ++:= 'de' ----> 'abcde'
c --:= 'a' ----> 'bcde'
c **:= 'd' ----> 'd'
s := [1,2,3] ----> list(3)
s |||:= s ----> list(6)
s |||:= s ----> list(12)
Run-time error 108 at line 16 in std01.icn
list expected
offending value: 'd'