How to map a Y intersection?
Having trouble figuring out the best way to map a difficult intersection. I have seen it done in differently, in the map. The highway and junction wiki pages offer no suggestions.
Imagine a road coming to a T-intersection, but each turning direction bears off, so it forms a Y-intersection (with the intersecting road still at the top of the Y), such that there is a impassible triangle between the three roads. Each road has traffic in both directions.
One way that I have seen this done is calling each branch the name of the original street.
Another way that I have seen it is designating one branch a highway=service and leaving it unnamed.
Yet another way is tagging one branch as a "highway link" and leaving it unnamed.
Generally, there are no housenumbers on either branch of the intersection, so it would not really matter for numbering, but my sense is a road name should be used for one road, whenever possible. I would like to know how best to handle this for routing.
1. [service road](http://www.openstreetmap.org/#map=17/42.86888/-70.86948&layers=T)
2. [duplicated road](http://www.openstreetmap.org/#map=18/42.97181/-70.76941&layers=T)
3. [service road](http://www.openstreetmap.org/#map=18/43.06270/-70.76997&layers=T)
4. [service road](http://www.openstreetmap.org/#map=18/42.94127/-70.79390&layers=T)
5. [duplicated road](http://www.openstreetmap.org/#map=18/42.93757/-70.83871&layers=T)
edit: as requested, above are links to the different methods mentioned. did not see any link roads, to show here, although they are rare the description does read like the best option.