William Waites wrote: > Possibly it is better to remove implication relationships amongst tags.
I doubt it. I think it is safe for highway=cycleway to imply bicycle=yes and motorcar=no, and for highway=motorway to imply foot=no, horse=no and bicycle=no. These are "obviously correct" assumptions, as they are part of the definition of the cycleway, or the motorway. So I think some implications are quite important, as they indicate some tags which it is unnecessary to apply. (I certainly don't feel like tagging oneway=no on most everything, for example). > Cycling is one thing, appropriateness of feet is another, no? There are basically 3 options: Imply foot=yes (and several equivalents) Imply foot=no No implication I feel that leaving it with no implication is a bad idea, because someone wishing to rely on the OSM data for a routing app will need to have a default for it anyway, either to route foot traffic along a cycleway, or not. So OSM might as well indicate which should be assumed. Of course, it would be possible to put an additional foot=* tag on every cycleway, but I think it's better to do this in only half (or less) of the cases, than to have to do it everywhere. That leaves us with yes or no. For the (OSM) definition of a highway=cycleway, it says "mainly or exclusively for bicycles" -- foot=yes would apply to those which are "mainly" for bicycles, while foot=no would apply to those which are "exclusively" for bicycles. The best assumption is the one which applies in the largest number of cases. I think that would be foot=yes. I know Andy disagrees with this, and I can see his point about foot=yes being wrong for some countries -- but I think it's better to have a default so it's easier to make assumptions about routing, than to require that all cycleways be tagged with an additional foot=* tag. -Alex Mauer "hawke" _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/cgi-bin/mailman/listinfo/talk
