[Tagging] Reviving the conditions debate

[Martin Vonwald]

Yes, short and readable (IMO), but how would you express a conditional maxspeed?

I suggested something similar some time ago, but people didnt seem to
be very happy with it. It was something like:
condition:<name>=<expression>
<anykey>:conditional(<name>)=<value>

The obvious drawback is, that you always need at least two tags.

Martin

2012/6/14 Pieren <pieren3 at gmail.com>:
> On Thu, Jun 14, 2012 at 8:38 AM, Colin Smale <colin.smale at xs4all.nl> wrote:
>
> Back to my idea to move all 'variables' to the value :
> Let say we create a new access keyword : "condition" (or
> "access_condition", "cond", "expr" or "whatever_you_like") suffixed by
> a number, eg. condition1, condition2, etc (unlimited but easy to
> parse; separator unnecessary).
> Then conditions are combined using a plain text language, not using
> ||, &&, ~, $ or any symbols only known by software programmers
> (important for readability by wide audience) eg. " and ", " or ", "
> not ", " in " like SQL.
>
> Examples:
>> Here's a test case. No motor vehicles mon-fri between 1600-1800 except
>> agricultural vehicles and good vehicles *in this direction*. Going the other
>> way the sign is similar but the times are between 0600 and 0900.
>
> access=yes   (this implies "agricultural=yes" and "goods=yes")
> condition1=Mo-Fr 16:00-18:00
> condition2=Mo-Fr 06:00-09:00
> motor_vehicle:forward=not condition1
> motor_vehicle:backward=not condition2
>
>> no motor vehicles except for loading/unloading by hgvs between 8pm
>> and 10am
>
> access=yes
> motor_vehicle=no
> condition1=loading         // improving current 'destination'
> condition2=10:00-20:00
> hgv=condition1 and not condition2
>
> Short, readable and easy, no ?
>
> Pieren
>
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