autofolder

autofolder is a single-element folding container that can be used to accumulate and/or select values (for example) in an ad-hoc fashion.

Rationale

Folding in Rust is accomplished via the [Iterator::fold] method, like so: rust iterator.fold(initial, function);

That works well when all the data we need is provided by a single iterator. If we have a more complex logic, fold can't be used. autofolder flips this structure by being built with the initial value and the folding function, and accepting values from various types of different sources during its lifetime.

Example

A more concrete example, using a [DynFolder]:

```rust use autofolder::*;

// Create an autofolder that sums u16 items into an usize output. let mut sum = DynFolder::::new(7, |a, b| a + b as usize);

// We can "fold-in" individual items: sum.fold(3);

// We can then peek at the running output: println!("Partial sum is {}", sum.as_ref());

// And still keep on folding by processing whole iterators: sum.extend((1..=5));

// And finally consume the autofolder to get the final output value: let total = sum.into_inner(); println!("Total sum is {}", total); ```