ai :: SearchSolver :: todo
They are the open nodes.
It is the nature of the queue that control how the solver works.
However, the methods SearchProblem::breadth_first, SearchProblem::depth_first,
and SearchProblem::astar takes care of its correct initialization.
# The currently open nodes to process.
# They are the open nodes.
#
# It is the nature of the queue that control how the solver works.
# However, the methods `SearchProblem::breadth_first`, `SearchProblem::depth_first`,
# and `SearchProblem::astar` takes care of its correct initialization.
private var todo: Queue[SearchNode[S, A]]
lib/ai/search.nit:238,2--244,42