> > the evaluation of boolean options in mkgmap is a bit confusing.
> > It is possible to specify e.g.
> > --drive-on-left
>
> This is the only documented form for this option.

Yes, that's true. I fear it was me who introduced the
format var=true|false with the documentation of
--remove-ovm-work-files
I also used that with splitter, e.g. keep-complete=true|false
I think I used it because it is common for tags.

> > do not have the same effect, and that is true for most
> > boolean options, because typically we use this kind of evaluation:
> > linkPOIsToWays = props.getProperty("link-pois-to-ways", false);
>
> Oh well, perhaps everyone disagrees with me then :) I guess all those
> options were added before the "no-" prefix was available however.

My understanding is that the "no-" prefix is similar to removing the option,
and with --check-roundabouts in combination with drive-on-right or drive-on-left
it doesn't have the wanted effect, as it triggers the automatic detection.
I agree that drive-on=right|left would be much better.

Gerd