Bug#720597: "apt-get --purge build-dep" broken in 0.9.11

[Andreas Metzler <ametzler@bebt.de>]

Package: apt
Version: 0.9.11
Severity: normal

Hello,

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(SID)root@argenau:/var/cache/apt/archives#
DEBIAN_FRONTEND=noninteractive eatmydata apt-get  --purge build-dep gnutls28
E: Command line option --purge is not understood
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This worked in versions up to and including 0.9.10

thanks, cu Andreas