public static ITraversable Find(this ITraversable item, EpubPath path)
{
ITraversable result = item;
while (path.ContainsKeys && result != null)
{
result = result.Child(path.FirstKey);
path = path.Rest;
}
return(result);
}
public static T SafeExecute <T>(this ITraversable item, EpubPath path, Func <ITraversable, T> action)
{
T safeExecuteImpl(ITraversable current, EpubPath currentPath)
{
if (currentPath.IsEmpty)
{
return(action(current));
}
using (var child = current.Child(currentPath.FirstKey))
{
return(safeExecuteImpl(child, currentPath.Rest));
}
}
// will ensure that all intermediate traversables are disposed
return(safeExecuteImpl(item, path));
}
public static object SafeGet(this ITraversable item, EpubPath path)
{
object safeGetImpl(ITraversable current, EpubPath currentPath)
{
if (currentPath.IsEmpty)
{
return(current.Value);
}
using (var child = current.Child(currentPath.FirstKey))
{
return(safeGetImpl(child, currentPath.Rest));
}
}
// will ensure that all intermediate traversables are disposed
return(safeGetImpl(item, path));
}
public static void SafeExecute(this ITraversable item, EpubPath path, Action <ITraversable> action)
{
void safeExecuteImpl(ITraversable current, EpubPath currentPath)
{
if (currentPath.IsEmpty)
{
action(current);
return;
}
using (var child = current.Child(currentPath.FirstKey))
{
safeExecuteImpl(child, currentPath.Rest);
}
}
// will ensure that all intermediate traversables are disposed
safeExecuteImpl(item, path);
}
public static void SafeRun(this ITraversable item, EpubPath path, string verb)
{
SafeExecute(item, path, x => x.Run(verb));
}