Usage

To create a MatchBox, you have to decide which characteristic must it work on.

box = MatchBox('colour')

A MatchBox instance can work on only one characteristic at once.

All entities that will be added and process by this matchbox, should have two attributes defined on them, which in combination create our characteristic. These are colour which should describe a colour and colour_match which should describe whether this entity is of that colour (or colours) or it’s not that colour (or colours). In the example let’s use entities defined by this collections.namedtuple():

   HomeObject = namedtuple('HomeObject', 'colour colour_match')

   chair = HomeObject('red', True)
   table = HomeObject('blue', True)
   wall = HomeObject('pink', False)
   paint_bucket = HomeObject('orange', True)

And add these entities to our box.

box.add(chair)
box.add(table)
box.add(wall)
box.add(paint_bucket)

match mehod performs simple set operation on passed collection, from which rejects a set of objects that MatchBox determine, won’t fit red colour:

home_objects = {chair, table, wall, paint_bucket}
box.match(home_objects, 'red')

Method match, will return set that consists of only chair and wall. chair because it explicitly says it’s red, and wall because it says it’s not pink, so it might as well be red or blue. Replacing red with pink in the above example will return an empty set from a box.