User:PesachZ/Road name inheritance View history

Revision as of 18:10, 19 March 2015 by Qwaletee (talk | contribs) (Lede - definition, a few more details, more direct language)

Unnamed segments (or no-name segments) are those segments where the None box has been ticked for the segment name. In routing instructions, they are often treated, for the current drive, as if they have the same name as the next named segment on the route. This is known as segment name inheritance. Any instruction for entering the segment will display and announce using the inherited name.

There are some situations where name inheritance does not apply, and the instruction is given without any name. The details of when inheritance occurs, and when it does not, are discussed at length in this article. The list of situations changed significantly in late 2014.

Unnamed segments also play a role in how Waze decides to create turn instructions, and, as a consequence, they may be used in creating wayfinders.

Current documentation

The USA wiki section for exit ramp names currently mentions in passing that segments with no name will use the next named segment in the route when they are announced in navigation.

If the exit off the main interstate or highway serves multiple exits further down the road, it may be advisable not to name the first exit ramp, but rather name only the ramps which are the first one to a distinct destination. The Waze client will give all the proper exit and keep left or right instructions to guide the driver to the correct exit, even if the first one is not named. That said, this should only be done if the signage for the first ramp is the same as that on the subsequent, named ramp.
Current basic understanding

Any segment which has the "No-Name" box checked can inherit the name of the next named segment. If this segment is at a turn in your route where there would be a turn instruction, the name of the next named segment on your route will be used. If there is no named segment on your route after this turn, you will only get the turn instruction, but no segment name. (Common with destinations inside complex parking lots)


New changes

The status-quo above still applies, and the following new changes do not affect  Freeways  or  Ramps .

For all other road types there are now two criteria which will prevent a segment from inheriting the next name of a segment along your route. If either of these criteria is met, you will just get the turn instruction without a street name displayed or spoken over TTS.

  • The combined total length of one or more consecutive No-Name segment(s) is over 400 meters long.
  • There are four or more consecutive no-name segments on the route.

Remember these new changes DO NOT apply to Freeways or ramps, a freeway or ramp interchange can have as many consecutive no-name segments as you'd like, and be as long as you'd like, and they will still all inherit the next name on your route.