[OSM-talk] Validator tags

[Matthias Julius]

sylvain letuffe <liste at letuffe.org> writes:

>> With the first I agree.  It is just not possible to define validation
>> rules that always produce the right results.  How is the validator to
>> know that this street really has no name?
>
> with a tag that say it has no name ?

With a tag to tell the validator not to complain about the fact that
the street has no name.

>
>> The second one is evil.  An example could be to tag "name= " to get
>> the validator to shut up without messing up rendered maps.
>
> in the no name proposal there are some with :
> name=__none__
> name=NONE
> name=
>
> If also find both three "evil"
> ( well, no "evil", but say "inapropriate" )

In general there is nothing wrong with a street with no name.  So a
name tag should not be required.  Special values for the name tag are
"evil" because the require special treatment in every application that
cares about names.  I don't want a routing software tell me to "turn
right onto NONE".

>
>> In general, there should only be ignore rules for specific tags that
>> have a "legitimate" use case.  
> I don't like the idea of "ignore" wether it is for bots or for validators
>
> "ignore=tagX" sounds too much to me that we don't have any information added
> while on the opposite :
> info=there_is_no_name_to_this_street
> look like we have an information 
>
> Even if the final result looks the same.
>
> I don't say it can happen, but suppose I'm working for a government and it 
> asks me to give a list of all street for which :
> - a sign with the name has been forgotten/stolen/destroyed
> - the local authority forgot to set a name to that street
>
> With the "ignore" logic, I won't be able to know why the street creator did 
> put that tag and would have to guess that "maybe" he has done so because the 
> street as no name. But It could also be because he wants the name not to be 
> renderer on a map, or he is unsure about the spelling but don't want it to be 
> red on the noname map...

Whatever the syntax is you won't know why someone chose not to include
a name tag.  The here discussed proposal is only about telling the
validator not to complain about the missing tag.  It is up to the
mapper to be reasonable and not just include ignore tags because all
those maplint warnings are too annoying.

And while it is not that important what the exact syntax is I think
"ignore" is perfectly OK because it is meant to tell validators to
ignore a specific instance of a street without name.

Matthias