callback: F)
-> io::Result<bool> {
if !is_directory(path.as_ref()) { //~ ERROR: unresolved name `is_directory`
+ //~| NOTE unresolved name
callback(path.as_ref(); //~ NOTE: unclosed delimiter
//~^ ERROR: expected one of
fs::create_dir_all(path.as_ref()).map(|()| true) //~ ERROR: mismatched types