To load the Grid Colouring construal and its associated 'playsheet', invoke JS-EDEN as at
and select Grid Colouring from the Project List.
This construal demonstrates a puzzle - each hexagon must be coloured, with no adjacent hexagons having the same colour, in such a way that each colour is used no more than 4 times. The construal includes observables that record the maximum number of occurrences of each colour. As initially set up, these observables are only used to monitor whether the puzzle has been successively solved - they do not constrain the selection of colours. Coloured buttons are displayed on each hexagon; these can be used to select a colour for the hexagon, or to restore to 'white'. As initially setup, the construal helps the user in solving the puzzle by only showing those buttons whose colour is not represented in an adjacent hexagon.