camlp4 software package provides Pre Processor Pretty Printer for OCaml, you can install in your Ubuntu 16.04 LTS (Xenial Xerus) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install camlp4
camlp4 is installed in your system.
Make ensure the camlp4 package were installed using the commands given below,
$ sudo dpkg-query -l | grep camlp4 *
You will get with camlp4 package name, version, architecture and description in a table
| Distro | Ubuntu 16 04 lts xenial xerus |
| Section | Development |
| Package | camlp4 |
| Version | 4.02.1+3-2 |
| Description | Pre Processor Pretty Printer for OCaml |
| Sub Section | Devel |