pub fn input_state(f: &fn(&str, FileInputState) -> bool) -> bool
Iterate directly over the command line arguments (no arguments
implies reading from stdin) with the current state of the iteration
provided at each call.
Fails when attempting to read from a file that can't be opened.
Prefix searches with a type followed by a colon (e.g.
fn:) to restrict the search to a given type.
Accepted types are: fn, mod,
struct (or str), enum,
trait, typedef (or
tdef).