refactor to make row traversal less annoying
refactor traverse_row_and_apply to allow writes to @solution
moved def for traverse* and applied it in one more spot
created traverse_col_and_apply
more refactoring
made lines longer
failing spec for a slightly more difficult board
hold up a tick, want to do one more refactor
start of refactor -- split out @solution into a separate class
start pulling in all references to @solution_state
more reeling in
y'know, like a fish.
SolutionState is mature enough to move out on its own
more refactoring
how the hell did this get missed?