-- |
-- Check whether the contents of a given 'Position' on the board suppose a block
-- for a given 'Player'. Only 'Stone's and 'Snorkel's from a different 'Player'
-- suppose a block.
isBlocking :: Player -> Maybe Piece -> Bool
isBlocking _ Nothing = False
isBlocking :: Player -> Maybe Piece -> Bool
isBlocking _ Nothing = False
isBlocking _ Nothing = False