[OSM-dev] tag implication database/library

[Per Eric Rosén]

Hi!

I have been making a few maps and applications using OSM data, mostly 
stored in postgis. In all cases, I have had to make custom carto rules /
database post-processing / application rules to compensate for multiple
ways of expressing the same information in OSM. Also, in some cases,
for taking care of which tag implies which information.

Is there some way of doing this just once; for example with some parseable 
implication database, and library? There is some "implies" on the wiki; 
but it's not completely chine-readable in a reliable way.

Such a database would probably also need being optionally keyed on 
country, "highway=cycleway" may imply different rules in different 
countries for example.

Would such a tool/database be useful, if not existing already?

I see two somewhat different usage cases, and I don't know if the same 
tool/database should be used for both:

1. normalizing a database before usage, for example changing
    "highway=ford" to "ford=yes" and moving to modern lifecycle tags

    (it could be argued that this shoud be done on the main OSM database
     by a bot, but data consumers could probably have larger or more
     specific needs of normalization compared to what can be agreed to do
     by changing the master OSM data)

2. getting specific implications without writing it to a database, for
    example highway=cycleway implies bicycle=yes, foot=yes in country X

best regards
Per Eric Rosén
--
^): Per Eric Rosén http://rosnix.net/~per/
/   per at rosnix.net GPG 7A7A BD68 ADC0 01E1 F560 79FD 33D1 1EC3 1EBB 7311