/// This is the main iterator trait. For more about the concept of iterators
/// generally, please see the [module-level documentation]. In particular, you
/// may want to know how to [implement `Iterator`][impl].
+///
+/// Note: Methods on infinite iterators that generally require traversing every
+/// element to produce a result may not terminate, even on traits for which a
+/// result is determinable in finite time.
///
/// [module-level documentation]: index.html
/// [impl]: index.html#implementing-iterator
//! ```
//!
//! This will print the numbers `0` through `4`, each on their own line.
+//!
+//! Bear in mind that methods on infinite iterators, even those for which a
+//! result can be computed in finite time, may not terminate. Specifically,
+//! methods such as [`min`], which in the general case require traversing
+//! every element in the iterator, are likely never to terminate for any
+//! infinite iterators.
+//!
+//! ```
+//! let positives = 1..;
+//! let least = positives.min().unwrap(); // Oh no! An infinite loop!
+//! // `positives.min` causes an infinite loop, so we won't reach this point!
+//! println!("The least positive number is {}.", least);
+//! ```
//!
//! [`take`]: trait.Iterator.html#method.take
+//! [`min`]: trait.Iterator.html#method.min
#![stable(feature = "rust1", since = "1.0.0")]