/// <summary>Returns the result of stacking <paramref name="mergePath"/> onto <paramref name="this"/></summary>
public static Maybe <IDirectedPath> MergePaths(this IDirectedPath @this, IDirectedPath mergePath)
{
if (@this == null || mergePath == null)
{
return(null);
}
while (mergePath.PathSoFar != null)
{
var hexside = mergePath.PathStep.HexsideExit;
var cost = mergePath.TotalCost - (mergePath = mergePath.PathSoFar).TotalCost;
@this = @this.AddStep(mergePath.PathStep.Coords, hexside, cost);
}
return(@this.ToMaybe());
}