document first steps for debugging

[maxheld83]

debugging is an unavoidable step in using software, especially open source software.

It'd be great to have some more resources on debugging strategies specifically on our website, or perhaps even some of our own ideas.

Below are some of the things I suggested in class today, but this may be altered or extended.

[maxheld83]

Steps to go through until the problem is solved:

1. Google the specific part(s) of the error message(s).
   Can be hard, because several programs may emit error messages, and you have to find the root cause error message.
   Good sources for answers are:
   • github.com (existing issues, do not lightly add new issues or comments; you have to be really sure that it's an actual bug with the program in question – github is not for support).
   • stackoverflow.com
2. Upgrade everything:
   • Operating System
   • R (infrequently)
   • RStudio
   • R packages
   • other packages via your system package manager (homebrew, chocolatey or apt-get or whatever)
   • LaTeX (if relevant), has its own package manager
3. Narrow down your example; create a minimum workable example (MWE) or reproducible example (reprex) (~same thing).
   Can be really stupid and tiny.
   Don't debug with your thorny, complete project as an example.
   Build up complexity from very simple beginnings to your actual case to figure out where the problem arose.
4. Disentangle the toolchain.
   Run through the components of your toolchain individually in the command line.
   Figure out what is the offending program, ideally what argument etc.