Error while sourcing slam_gmapping in ROS Melodic

edit

I have got the slam_gmapping package from https://github.com/OpenSLAM-org/openslam_gmapping.git Now when I try to source the workspace in ROS Melodic, I get the following output, which is throwing an error:

shaunak@robokits:~/catkin_ws$ rosdep install --from-paths src -i -y
ERROR: the following packages/stacks could not have their rosdep keys resolved
to system dependencies:
slam_gmapping: Cannot locate rosdep definition for [openslam_gmapping]
gmapping: Cannot locate rosdep definition for [openslam_gmapping]

I also tried https://github.com/ros-perception/slam_gmapping.git, but came to know that it is built till ROS Hydro only.

Am I facing this issue due to my latest ROS Melodic Version? Is there any slam_gmapping source available for ROS Melodic? If yes, kindly share it.

Edit: @gvdhoorn : Thank you for sharing #q300480. I have not used docker yet. In fact, it's a new term for me. I was about to execute the following commands:

$ docker run -it --rm ros:melodic
(docker) $ apt update
(docker) $ rosdep update
(docker) $ mkdir -p /ros_ws/src
(docker) $ cd /ros_ws
(docker) $ git clone https://github.com/ros-perception/openslam_gmapping src/openslam_gmapping
(docker) $ git clone https://github.com/ros-perception/slam_gmapping src/slam_gmapping
(docker) $ rosdep install --from-paths src/ -i
(docker) $ catkin_make

But I had to sudo the docker run -it --rm ros:melodic command and it ended like this:

shaunak@robokits:~$ sudo docker run -it --rm ros:melodic
root@583c78ce75be:/#

instead of

$ docker run -it --rm ros:melodic
(docker) $

Please confirm whether I should proceed further or not.

I also want to know, if I can work in root@583c78ce75be:/# , whether I can use my already existing workspace instead of creating a new one as per here. If I can not, then I can not work on my existing workspace that has many other packages as well. So kindly clarify it because as per my understanding, I find no point in setting up two different workspaces having separate sections of my packages.

Shaunak Agastya Vyas (TINU)