fer@ROUTER-VB:~/Test$ ghc-pkg list
/var/lib/ghc/package.conf.d
   Cabal-1.14.0
   array-0.4.0.0
   base-4.5.1.0
   bin-package-db-0.0.0.0
   binary-0.5.1.0
   bytestring-0.9.2.1
   containers-0.4.2.1
   deepseq-1.3.0.0
   directory-1.1.0.2
   extensible-exceptions-0.1.1.4
   filepath-1.3.0.0
   ghc-7.4.2
   ghc-prim-0.2.0.0
   haskell2010-1.1.0.1
   haskell98-2.0.0.1
   hoopl-3.8.7.3
   hpc-0.5.1.1
   integer-gmp-0.4.0.0
   old-locale-1.0.0.4
   old-time-1.1.0.0
   pretty-1.1.1.0
   process-1.1.0.1
   rts-1.0
   template-haskell-2.7.0.0
   time-1.4
   unix-2.5.1.1
/home/fer/.ghc/x86_64-linux-7.4.2/package.conf.d
   ReadArgs-1.2.1
   SHA-1.6.1
   Test-0.0.0
   aeson-0.6.0.2
   ansi-terminal-0.5.5.1
   asn1-data-0.7.1
   attoparsec-0.10.2.0
   attoparsec-conduit-0.5.0.3
   authenticate-1.3.2
   base-unicode-symbols-0.2.2.4
   base64-bytestring-1.0.0.0
   base64-conduit-0.5.1
   basic-prelude-0.3.1.0
   blaze-builder-0.3.1.0
   blaze-builder-conduit-0.5.0.3
   blaze-html-0.5.1.3
   blaze-markup-0.5.1.4
   byteorder-1.0.3
   case-insensitive-0.4.0.3
   cereal-0.3.5.2
   certificate-1.3.3
   cipher-aes-0.1.5
   classy-prelude-0.4.2
   classy-prelude-conduit-0.4.2
   clientsession-0.8.0.1
   conduit-0.5.5
   cookie-0.4.0.1
   cprng-aes-0.3.1
   cpu-0.1.1
   crypto-api-0.10.2
   crypto-conduit-0.4.2
   crypto-pubkey-types-0.2.0
   crypto-random-api-0.1.0
   cryptocipher-0.3.7
   cryptohash-0.8.1
   css-text-0.1.1
   data-default-0.5.0
   date-cache-0.3.0
   dlist-0.5
   email-validate-0.3.2
   entropy-0.2.1
   failure-0.2.0.1
   fast-logger-0.3.1
   file-embed-0.0.4.6
   fsnotify-0.0.4
   ghc-paths-0.1.0.9
   hamlet-1.1.2
   hashable-1.1.2.5
   hinotify-0.3.5
   hjsmin-0.1.4
   http-conduit-1.8.5.1
   http-date-0.0.3
   http-reverse-proxy-0.1.0.7
   http-types-0.7.3.0.1
   language-javascript-0.5.7
   largeword-1.0.4
   lifted-base-0.2.0.2
   mime-mail-0.4.1.2
   mime-types-0.1.0.0
   monad-control-0.3.1.4
   monad-logger-0.2.3.1
   mtl-2.1.2
   network-2.4.0.1
   network-conduit-0.6.2
   optparse-applicative-0.4.3
   parsec-3.1.3
   path-pieces-0.1.2
   pem-0.1.2
   persistent-1.1.0.1
   persistent-sqlite-1.1.0
   persistent-template-1.1.1
   pool-conduit-0.1.1
   primitive-0.5.0.1
   project-template-0.1.1
   pureMD5-2.1.2.1
   pwstore-fast-2.3
   random-1.0.1.1
   ranges-0.2.4
   regex-base-0.93.2
   regex-compat-0.95.1
   regex-posix-0.95.2
   resource-pool-0.2.1.1
   resourcet-0.4.4
   safe-0.3.3
   semigroups-0.8.4.1
   shakespeare-1.0.2
   shakespeare-css-1.0.2
   shakespeare-i18n-1.0.0.2
   shakespeare-js-1.1.0
   shakespeare-text-1.0.0.5
   silently-1.2.4.1
   simple-sendfile-0.2.10
   skein-0.1.0.10
   socks-0.4.2
   split-0.2.1.1
   stm-2.4.2
   stringsearch-0.3.6.4
   syb-0.3.7
   system-fileio-0.3.10
   system-filepath-0.4.7
   tagged-0.4.4
   tagsoup-0.12.8
   tar-0.4.0.1
   text-0.11.2.3
   tls-1.0.3
   tls-extra-0.5.1
   transformers-0.3.0.0
   transformers-base-0.4.1
   unix-compat-0.4.0.0
   unix-time-0.1.4
   unordered-containers-0.2.2.1
   utf8-light-0.4.0.1
   utf8-string-0.3.7
   vault-0.2.0.1
   vector-0.10.0.1
   void-0.5.10
   wai-1.3.0.1
   wai-app-static-1.3.0.5
   wai-extra-1.3.0.5
   wai-logger-0.3.0
   warp-1.3.6
   word8-0.0.3
   xml-conduit-1.0.3.3
   xml-types-0.3.3
   xss-sanitize-0.3.2
   yaml-0.8.1.1
   yesod-1.1.7
   yesod-auth-1.1.2.2
   yesod-core-1.1.6.1
   yesod-default-1.1.3
   yesod-form-1.2.0.2
   yesod-json-1.1.2
   yesod-persistent-1.1.0.1
   yesod-routes-1.1.1.1
   yesod-static-1.1.1.1
   zlib-0.5.4.0
   zlib-bindings-0.1.1.2
   zlib-conduit-0.5.0.3
fer@ROUTER-VB:~/Test$ ghc-pkg list | grep happy