public static IProjectItemNode AddItem(this IFolderNode folder, string path) => folder.AsContainerNode().AddItem(path);
public static IProjectItemNode AddItem(this IProjectNode project, string path) => project.AsContainerNode().AddItem(path);
public static IFolderNode CreateFolder(this IFolderNode folder, string name) => folder.AsContainerNode().CreateFolder(name);
public static IFolderNode CreateFolder(this IProjectNode project, string name) => project.AsContainerNode().CreateFolder(name);