Don't mix tabs and spaces indentation?

[fingolfin]

Your source code currently freely mixes tabs and spaces for indentation. That makes it hard to read the code unless one has the editor set to the exact correct tab width.

I would recommend to use either tabs or spaces for indentation, but never mix them.

BTW to avoid a misunderstanding, this like my other recent issues is independent from adding the package to the GAP distribution, i.e., I am not waiting for these issues to be resolved (only the test failure needs to be resolved), I am just adding them because I observer them just now while looking at your code again.