[OSM-talk] Tagging climbing routes and scrambles

[Steve Hill]

On Thu, 24 Apr 2008, Ari Torhamo wrote:

> on the other hand because some of the argumenting has been based on
> how the use of namespaces would affect the inexperienced OSM:ers - like
> me.

Thanks for your input - you're *exactly* the sort of person we need to 
hear from, rather than reasoning on a purely technical level or making 
assumptions about how good/bad things are for inexperienced people.

> I had to go to
> Wikipedia to find out what a namespace stands for
    ...
> I do understand the idea of a namspace
> now, but I would need to know more about the practical implementation to
> know if using namespaces would feel too complicated to me.

Well, it is important to realise that there is no real need to know what a 
namespace is to use namespaced tags, and there isn't really any 
implementation as such - it is purely a convention for tag names.  So 
instead of having a tag such as "grade", which is fairly meaningless 
without further context (which is provided by the other tags on the node), 
you call the tag "climbing:grade", making it really obvious that it is a 
climbing grade (i.e. how difficult the climbing route is).  Nothing is 
different, other than the tag name.

In my view, this simplifies things since it makes tags unique - you know 
that "climbing:grade" is always going to be a climbing grade and you need 
no further information to do things like look up the definition of the tag 
on the wiki.

For people who don't know or care what a namespace is, this is really no 
different from the existing system - you want to tag something so you look 
it up in the wiki to see what the convention is and the wiki tells you 
what tag name to use.

> in a sence that same tags might
> default to different tag properties, depending on the context.

This is a good point.  I'm not sure how well it would apply in practice 
though.  At the moment, the defaults for certain tags do change based on 
quite a few factors.

> It would be
> interesting to see a few real life scenarios, perhaps a best case,
> typical case and a worst case, where one would be able to compare the
> case of using namespaces to not using them.

This is an interesting idea (although I don't think anyone is suggesting 
changing any existing tags to name-spaced ones at the moment - the 
discussion is really revolving around new tags).  I'm not sure how you 
would define "best case" and "worst case" though, and you really need to 
consider the system as a whole rather than isolated cases because the main 
reason for namespaces is to avoid ambiguity with other tags used elsewhere 
on the system.

  - Steve
    xmpp:steve at nexusuk.org   sip:steve at nexusuk.org   http://www.nexusuk.org/

      Servatis a periculum, servatis a maleficum - Whisper, Evanescence