[Tagging] Various alt_name values?

moltonel 3x Combo moltonel at gmail.com
Thu Nov 27 11:59:13 UTC 2014

On 27/11/2014, Colin Smale <colin.smale at xs4all.nl> wrote:
> Big +1 for that.


On what do you base your assumption that nominatim is the only
software implementing numbered keys ? How is documenting what a major
osm software does a bad thing ? For better or worse, the numbered keys
scheme sees a good bit of use according to taginfo (it's harder to get
numbers on the semicolon scheme).

> To me, solving it from the root means formalising the use of the
> semicolon as a value separator, and cracking some hard nuts like how to
> handle a legitimate semicolon in the data itself and how to handle the
> quoting/escaping that that will involve.

To me, the semincolon scheme as a general solution is a very bad idea,
and I'd hate to see it "formalised" to the exclusion of other schemes.
That's because it's so easy for data users to get it wrong. Either the
data user forgets to do the split, or he does it when it wasn't the
mapper's intent, or litteral semincolons in the data get in the way.

In contrast, the numbered keys scheme is a bit ugly and harder to use,
but it's very unlikely that a data user would get it wrong. At worse,
only the first value will be picked up, which is a more gracefull
degradation than the semicolon worst-case.

It's still an unsatisfactory solution, and I've been arguing for
direct support of multi-value keys in the osm data model, but that's a
much longer-term prospect.

> But let's do it once and once only, so it can be used consistently
> across all the editors and consumers in our ecosystem.

Agreed. And that's why I don't like the semiclon scheme, because I
can't imagine it being used in an error-free consistent manner.

PS: whiile we're talking about multiple values for the alt_name key
specificaly... WTF ? "alt_name" is already a way to encode 1
additional value for the "name" key, so if you're describing a scheme
to add any number of additional values, apply this scheme to "name"
and not "alt_name".

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