[Tagging] Reviving the conditions debate

[Tobias Knerr]

On 14.06.2012 08:38, Colin Smale wrote:
> My concern with this is that it may become unwieldy and cumbersome with
> anything beyond fairly trivial cases such as your maxspeed example.

For me, the goal is to make the common cases *easy*, and the rare
complex cases *possible*.

> For the human audience who can't grasp it yet there are millions of
> books and websites. The way it is presented in map editors will be
> extremely critical in any case.

It's far easier to build a visual editor if you only need to support a
limited subset of boolean logic. For example, the "filter" editor in my
mail client (Thunderbird) is limited to a subset of boolean logic as
well, for the same reason.

> 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.
>
> What would this look like using only AND operators?

motor_vehicle:forward:(Mo-Fr 16:00-18:00) = agricultural
goods:forward:(Mo-Fr 16:00-18:00) = yes

motor_vehicle:backward:(Mo-Fr 16:00-18:00) = agricultural
goods:backward:(Mo-Fr 06:00-09:00) = yes

Again using "Extended conditions for access tags".

Tobias