[digisign]

Hmm, needs additional semi-colons.

[23david]

where?

I was trying to use the example given... Here's another, smaller example:

  # install wget without artifacts
  RUN set -e; \
    apt-get update; \
    apt-get install -y wget; \
    apt-get clean; \
    rm -rf /var/lib/apt/lists/*

[e12e]

I think parent meant you trade two &&s for one ;.

Personally I also don't think the meaning is as clear, and you now need to maintain the top line if you cut'n'paste. I suppose it's a matter of taste.