[OSM-newbies] Creating a cul-de-sac

[Denver Gingerich]

I have seen several methods of inputting a cul-de-sac into OSM, but no
particular method seems generally accepted.  Here are a couple
examples:

1. http://www.openstreetmap.org/index.html?mlat=43.53505746903256&mlon=-80.29595502001675&zoom=16
2. http://www.openstreetmap.org/index.html?mlat=43.49095032394568&mlon=-80.54953961922436&zoom=16

In #1, the cul-de-sacs are created with a single way that meets
itself, forming a "P".  In #2, the cul-de-sacs are created with two
ways, one for the street leading up to the loop at the end
(highway=residential) and one for the loop at the end
(highway=residential, junction=roundabout, oneway=yes).  Neither of
these seem entirely correct.  #1 seems wrong because it misses the
one-way nature of the loop at the end and #2 seems wrong because the
loop isn't really a junction or a roundabout (it only has one street
connecting to it).

Is there a generally accepted method for creating cul-de-sacs that
solves these problems?

On a related note, should cul-de-sacs be labeled noexit=yes?

Denver