Re: [OSM-dev] Recursive relations
Shaun McDonald sh...@shaunmcdonald.me.uk writes: On 13 Sep 2009, at 10:56, Andrew M. Bishop wrote: In OSM a relation can contain other relations but it seems that there is nothing to check that a relation doesn't contain itself. I can't think of any legitimate reason that it should be allowed though. From a data and technical point of view this has always been possible in the API intentionally. It's just that no one has come up with a good use for it yet. Since I can't see any purpose that it can serve for a route or a boundary I have edited the relations listed in my original e-mail and removed the self-recursion. As others have pointed out JOSM warned me that the relations were self-recursive when I edited them and offered to automatically fix the problem. The JOSM validator doesn't check for this condition though. For reference I created two changesets, one for route relations 12179, 15852, 80545, 101440, 163368, 165638, 167468, 170290 and one for boundary relation 57535. There are no other self-recursive relations within the UK. For the route relations the changeset is 2478746 and for the boundary relation the changeset is 2478757. Within the UK alone the following route relations all contain themselves: 12179 15852 80545 101440 163368 165638 165638 167468 168189 170290 170290 Also within the UK there is one boundary relation that contains itself: 57535 -- Andrew. -- Andrew M. Bishop a...@gedanken.demon.co.uk http://www.gedanken.demon.co.uk/ ___ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev
[OSM-dev] Recursive relations
In OSM a relation can contain other relations but it seems that there is nothing to check that a relation doesn't contain itself. I can't think of any legitimate reason that it should be allowed though. For example relation 15852 has contained itself since version 108 which was created at the beginning of July (changeset 1754423). Within the UK alone the following route relations all contain themselves: 12179 15852 80545 101440 163368 165638 165638 167468 168189 170290 170290 Also within the UK there is one boundary relation that contains itself: 57535 Obviously it is possible to ignore these when parsing the data (which is what I do and what alerted me to them in the first place) but it would be better if it didn't happen. This is probably something that the OSM editors should warn users about when they try to create such a relation. Is there somebody that can find and fix all such relations on the server (if they have no legitimate use)? Obviously self-recursion is easy to find; there might be mutually recursive relations as well but I haven't looked for them. -- Andrew. -- Andrew M. Bishop a...@gedanken.demon.co.uk UK OpenStreetMap Route Relations: http://www.gedanken.org.uk/mapping/osm-routes/route.html UK OpenStreetMap Boundary Relations: http://www.gedanken.org.uk/mapping/osm-boundaries/boundary.html ___ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev
Re: [OSM-dev] Recursive relations
From a data and technical point of view this has always been possible in the API intentionally. It's just that no one has come up with a good use for it yet. Shaun On 13 Sep 2009, at 10:56, Andrew M. Bishop wrote: In OSM a relation can contain other relations but it seems that there is nothing to check that a relation doesn't contain itself. I can't think of any legitimate reason that it should be allowed though. For example relation 15852 has contained itself since version 108 which was created at the beginning of July (changeset 1754423). Within the UK alone the following route relations all contain themselves: 12179 15852 80545 101440 163368 165638 165638 167468 168189 170290 170290 Also within the UK there is one boundary relation that contains itself: 57535 Obviously it is possible to ignore these when parsing the data (which is what I do and what alerted me to them in the first place) but it would be better if it didn't happen. This is probably something that the OSM editors should warn users about when they try to create such a relation. Is there somebody that can find and fix all such relations on the server (if they have no legitimate use)? Obviously self-recursion is easy to find; there might be mutually recursive relations as well but I haven't looked for them. -- Andrew. -- Andrew M. Bishop a...@gedanken.demon.co.uk UK OpenStreetMap Route Relations: http://www.gedanken.org.uk/mapping/osm-routes/route.html UK OpenStreetMap Boundary Relations: http://www.gedanken.org.uk/mapping/osm-boundaries/boundary.html ___ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev ___ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev
Re: [OSM-dev] Recursive relations
This is probably something that the OSM editors should warn users about when they try to create such a relation. JOSM doesn't allow to create recursive relations, but it accepts them when they are present in the data. -- Karl -Ursprüngliche Nachricht- Von: dev-boun...@openstreetmap.org [mailto:dev-boun...@openstreetmap.org] Im Auftrag von Andrew M. Bishop Gesendet: Sonntag, 13. September 2009 11:56 An: dev@openstreetmap.org Betreff: [OSM-dev] Recursive relations In OSM a relation can contain other relations but it seems that there is nothing to check that a relation doesn't contain itself. I can't think of any legitimate reason that it should be allowed though. For example relation 15852 has contained itself since version 108 which was created at the beginning of July (changeset 1754423). Within the UK alone the following route relations all contain themselves: 12179 15852 80545 101440 163368 165638 165638 167468 168189 170290 170290 Also within the UK there is one boundary relation that contains itself: 57535 Obviously it is possible to ignore these when parsing the data (which is what I do and what alerted me to them in the first place) but it would be better if it didn't happen. This is probably something that the OSM editors should warn users about when they try to create such a relation. Is there somebody that can find and fix all such relations on the server (if they have no legitimate use)? Obviously self-recursion is easy to find; there might be mutually recursive relations as well but I haven't looked for them. -- Andrew. -- Andrew M. Bishop a...@gedanken.demon.co.uk UK OpenStreetMap Route Relations: http://www.gedanken.org.uk/mapping/osm-routes/route.html UK OpenStreetMap Boundary Relations: http://www.gedanken.org.uk/mapping/osm-boundaries/boundary.html ___ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev ___ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev
Re: [OSM-dev] Recursive relations
Karl Guggisberg wrote: This is probably something that the OSM editors should warn users about when they try to create such a relation. JOSM doesn't allow to create recursive relations, but it accepts them when they are present in the data. JOSM has in the past accepted recursive relations and it is very likely that people still have versions running that do so. Maarten -Ursprüngliche Nachricht- Von: dev-boun...@openstreetmap.org [mailto:dev-boun...@openstreetmap.org] Im Auftrag von Andrew M. Bishop Gesendet: Sonntag, 13. September 2009 11:56 An: dev@openstreetmap.org Betreff: [OSM-dev] Recursive relations In OSM a relation can contain other relations but it seems that there is nothing to check that a relation doesn't contain itself. I can't think of any legitimate reason that it should be allowed though. For example relation 15852 has contained itself since version 108 which was created at the beginning of July (changeset 1754423). Within the UK alone the following route relations all contain themselves: 12179 15852 80545 101440 163368 165638 165638 167468 168189 170290 170290 Also within the UK there is one boundary relation that contains itself: 57535 Obviously it is possible to ignore these when parsing the data (which is what I do and what alerted me to them in the first place) but it would be better if it didn't happen. This is probably something that the OSM editors should warn users about when they try to create such a relation. Is there somebody that can find and fix all such relations on the server (if they have no legitimate use)? Obviously self-recursion is easy to find; there might be mutually recursive relations as well but I haven't looked for them. -- Andrew. -- Andrew M. Bishop a...@gedanken.demon.co.uk UK OpenStreetMap Route Relations: http://www.gedanken.org.uk/mapping/osm-routes/route.html UK OpenStreetMap Boundary Relations: http://www.gedanken.org.uk/mapping/osm-boundaries/boundary.html ___ dev mailing list dev@openstreetmap.org http://lists.openstreetmap.org/listinfo/dev
