Expand description
§size_guess
Provides a one-line way to estimate the upper size of an iterator.
The guess is based on the iterator’s upper bound hint, if present; otherwise, it is based on the lower bound.
§Usage
use size_guess::SizeGuess;
// exact size iterators will return an accurate guess
let iter = 1..10;
let guess = iter.size_guess();
assert_eq!(guess, iter.len());
// unbounded iterators will return the lower bound, which may be very large
let iter = std::iter::repeat(());
let guess = iter.size_guess();
assert_eq!(guess, usize::MAX);