[Freeciv-Dev] Re: (PR#12873) OR Requirements for Buildings

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

<URL: http://bugs.freeciv.org/Ticket/Display.html?id=12873 >

Vasco Alexandre da Silva Costa wrote:

> So an answer is: Reverse Polish Notation aka postfix notation. Like this:
> 
> sreqs    =
>     { "type", "name", "range"
>       "Tech", "Electronics", "Player"
>       "Building", "Factory", "City"
>       "Operator", "AND"
>       "Terrain", "Mountains", "Adjacent"
>       "Special", "River", "Adjacent"
>       "Operator", "OR"
>       "Operator", "AND"
>     }
> 
> Super reqs. You can still store the expression as a list, and with a
> stack you can calculate the expression pretty easily.

Not that I'm in favor of such craziness but prefix notation would be
better.  Just reverse the above list and you have prefix notation.

-jason