pub trait Peekable<T> {
fn peek(&self) -> bool;
}Ports that can peek
fn peek(&self) -> boolReturns true if a message is available
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).