Parsing error / silent fail on unmatched brackets

[Leroy Tennison]

            addresses:
              - a.b.c.d/29
              - a.b.c.e/29

works (note fourth octet is d and e)

but

            addresses:
              - a.b.c.d/29
              - a.b.c.e/29]

doesn't report an error but also doesn't assign a.b.c.e/29 (note the trailing ] on the second line)

[Mathieu Trudel-Lapierre (cyphermox)]

Thanks!

This is quite a fun bug; well defined and should be interesting to address. Triaging.