The Overpass API language guide does allow for logical operators when matching a tag value... for example:["name"~"holtorf|Gielgen"]
will return whatever object has either name=holtorf or name=Gielgen.
You can also combine conditions and they will become an AND... so for example:
["name"]["name"="holtorf"]
. Means to search for things that have the tag "name" and that the tag name is equal to "holtorf".
But what I want is an OR operator... something like:
["name"="holtorf"]|["name:eng"holtorf"]
In my specific application, I just want to know if there is ANY tag that start with "name"... so what I would like to do is put this into the API: ["^name"]
(cause in this API "^" means "starts with"). But of course it searches for literal "^name" and returns nothing.
Is there some workaround?
There is no OR operation, but you can use UNION
There is also a DIFFERENCE and negotiation http://wiki.openstreetmap.org/wiki/Overpass_API/Overpass_QL#Difference
And in your particular case, you could use key-value regexpressions matching. http://wiki.openstreetmap.org/wiki/Overpass_API/Overpass_QL#Key.2Fvalue_matches_regular_expression_.28.7E.22key_regex.22.7E.22value_regex.22.29