Turn restrictions and ambiguity

Help and support
1

I am parsing turn restrictions from the OSM files and have run into this situation, which I expect may occur. 2 ways are intersecting in a normal 4-way junction. Sharing a node in the junction. Now imagine a turn restriction described as from way1 to way2 at the node. Even if I know it is a banned left-turn, I can not tell from which direction it is. There are 2 possible banned left-turns depending upon which direction I am coming from way1. Is there a rule which prevents this from happenning?

Sample intersection:

But no turn restrictions here (so far…..)

2

I’m not clear as to what exactly you are asking. However, this guide might be a good introduction to turn restrictions Explicit Turn Restrictions | Mapbox

3

You have to split both ways at the intersection node and then create the turn-restrictions.

Turn-restrictions w/o split ways does not work.

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4

Thanks, after trying to add turn restrictions, I can see ways are automatically split.

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