// Names of public modules in libstd and libcore don't accidentally get into prelude // because macros with the same names are in prelude. fn main() { env::current_dir; //~ ERROR use of undeclared crate or module `env` type A = panic::PanicInfo; //~ ERROR use of undeclared crate or module `panic` type B = vec::Vec<u8>; //~ ERROR use of undeclared crate or module `vec` }