008+ prompt> [$a has been removed, removing watchpoint]
009+ [Script ended normally]
008- prompt> [Breaking on watchpoint $a]
009- Old value:
010- New value: aa
011- >00005: $a[1] = "b";
012- 00006:
013- prompt> [Breaking on watchpoint $a]
014- Old value: aa
015- New value: ab
016- >00006:
017- prompt> [$a has been removed, removing watchpoint]
018- [Script ended normally]
019- prompt>