Data.Puzzles.GridShape
type Coord
type Size
data Square
data Dir
data Edge a
data Dir'
data Edge' a
class Dual2D a
type Key k
type Dual' k
data C
data N
class FromCoord a
class ToCoord a
edge
edge'
edgeBetween
edgeBetween'
orient
ends'
revEdge
edges
edgesM
ends
edgeSize
unorient
dualE
vertexNeighbours
edgeNeighbours