Add a examples to the module docs

[dns2utf8]

Hi

I wanted to add examples to the docs. My first example works as I expected.

My second example behaves very strange. It compiles when I use i32 as the type of the Range<T>.
With any other type such as usize, u64 or i64 it does not compile.
Do you have an idea how to fix it?

Regards

---

Error message:

---- src/range.rs - range::Iter (line 23) stdout ----
        error[E0599]: no method named `zip` found for type `rayon::range::Iter<i64>` in the current scope
 --> src/range.rs:6:20
  |
6 |                   .zip(0..25)
  |                    ^^^
  |
  = note: the method `zip` exists but the following trait bounds were not satisfied:
          `&mut rayon::range::Iter<i64> : std::iter::Iterator`

[cuviper]

Range<usize> should work, but it's expected that i64 and u64 ranges don't implement IndexedParallelIterator, for the same reason they don't implement std::iter::ExactSizeIterator: a 64-bit range may overflow a usize length on 32-bit platforms.

[dns2utf8]

Ah, I did not know that. I added a note to the docs.

[cuviper]

I cherry-picked your CI fixes in #436. If you'll please rebase the rest of your changes, we can see how CI fares now.

[dns2utf8]

Rebased and tested. Thank you for the cerry-picking.

[cuviper]

I notice in both examples you use .fold(...).sum(), when just .sum() should work fine. Was this intentional?

[cuviper]

We should have a blank doc-line between the intro and additional description. Or if you want it as one intro paragraph, then it needs punctuation between the clauses.

Also, ParallelIterator is implemented for range::Iter<T> of all integer types. The difference is just that i64 and u64 don't implement IndexedParallelIterator, which you'd need for zip, for example.

[dns2utf8]

Hm the fold().sum() was a strange idea.

[dns2utf8]

Would you like me to squash the commits?

[cuviper]

Small clarification, please: "Not implemented for u64 and i64 ranges."

[cuviper]

Yeah, let's squash this one to its final state, thanks!

[dns2utf8]

Fixed and squashed. Greetings from the RustFest impl days

[cuviper]

Thanks!