[Tagging] Reviving the conditions debate

[Pieren]

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