FTBFS against ocaml 4.02

There is a new version of ben in Debian unstable, awaiting merge, which is probably going to fix this bug.

I got this you guys

Thanks for the merge! Yes, it fixes the FTBFS nicely.

This bug was fixed in the package ben - 0.7.3ubuntu1

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ben (0.7.3ubuntu1) xenial; urgency=low

  * Merge from Debian unstable. Remaining changes:
    - Show Ubuntu logo.
    - Allow configs to request the Packages/Sources files are not
      redownloaded (so that we can download once and for all at the start).
    - Add an Ubuntu template.
    - Tolerate templates with buildds or critical_bugs entries that return
      None.
  * Fixes FTBFS (LP: #1515019)

ben (0.7.3) unstable; urgency=medium

  * Port to tyxml 3.5
  * Tell curl to follow HTTP redirects

ben (0.7.2) unstable; urgency=medium

  * Use date from last changelog entry in generated documentation to ensure
    a reproducible build.
  * Use http://httpredir.debian.org/debian as a default Debian mirror.
  * Update instructions in example file (Closes: #797100).
  * Set section to "devel" (Closes: #800390).
  * Drop Benl_arg module and use OCaml's Arg module. This change bumps
    minimal required version for OCaml to 4.01.

ben (0.7.1) unstable; urgency=medium

  [ Paul Wise ]
  * cdn.debian.net has been deprecated, replace it with http.debian.net

  [ Mehdi Dogguy ]
  * Ignore potential errors when deleting lock file
  * Use FileUtil.rm instead of calling /bin/rm
  * Replaces uses of Benl_core.list_iteri with List.iteri, which requires
    OCaml >= 4.0.
  * Call dose-debcheck with --deb-native-arch
  * Make build reproducible (Closes: #792054)
  * Add a note about order of command-line flags in documentation (Closes: #747875)
  * Add Json output format in monitor (Closes: #747883)
  * Drop --text, --xhtml and --color in favor of --output-format|-f

  [ Emilio Pozuelo Monfort ]
  * Fix buildd.debian.org compact links

  [ Simon McVittie ]
  * Add a new Partial category for packages that are both good and bad
    (Closes: #795314).

ben (0.7.0) unstable; urgency=medium

  * Add --no-clean to "ben tracker" to leave unknown generated
    HTML files.
  * "ben tracker" will clean up the HTML directory by default from
    now on.
  * Add ability to read uncompressed files by specifying "plain",
    "no" or "none" as a compression format.
  * Remove --output-type from "ben tracker". Support for other output
    types didn't exist anyway and is not planned.
  * Simplify queries so that processing is, a bit, faster.
  * Make templates directory configurable through BEN_TEMPLATES_DIR
    environment variable.
  * Automatically set correct date and revision when generating refman.
  * Bump magic number to BENA0902 because of change in internal format
    of cache file. This requires regeneration of .cache files.
  * Ben should not define any of the modules exported by its library.
    Update the nodefined-map for Ben accordingly.
  * Add libocamlnet-ocaml-dev to Build-Depends, needed by Ben_monitor
    through usage of Netencoding (Closes: #750327).
  * Using -stdin, ben monitor will read its input file from the
    standard input (Closes: #747887).
  * Document how ben query makes the difference between Packages and
    Sources files (Closes: #747879).
  * Use Arg module to process CLI arguments.
  * Parallelize (using ParMap) ben's processing in all frontends, except
    query....