On Sat, Apr 25, 2015 at 3:45 PM, Peng Yu <pengyu.ut@gmail.com> wrote:
Why cabal install print so many irrelevant messages? Is it better to
follow Unix "Rule of Silence" to only print usage error messages?

This is not an irrelevant message:

asn1-parse-0.9.0 (reinstall) changes: text-1.2.0.4 added

It's an indication that things are about to go very wrong, as indeed they did. In fact, the errors you got indicate quite a lot of problems with your Haskell installation; you apparently have a bunch of broken packages.

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