Document from_iter methods and

[alamb]

Is your feature request related to a problem or challenge? Please describe what you are trying to do.
Users can create arrow arrays in one of two ways:

1. Directly from an Iterator or vec (via methods such as from_iter and this we can use collect())
2. Using a builder (something that implements ArrayBuilder)

Typically the from_iterator method is both easier to use and faster, but it is not well documented in the doc strings

Describe the solution you'd like

1. Add doc examples for from_iter methods (we can file additional issues for subsets of these iterators)
2. Add doc examples for the builders (such as https://docs.rs/arrow/4.0.0/arrow/array/struct.BooleanBuilder.html) and also link to the from_iter methods

[novemberkilo]

Am also good to run with this. Please assign to me as appropriate. Thanks @alamb

[alamb]

BTW @novemberkilo there are probably lots of good examples to from the tests that can be pulled into the doc examples

[novemberkilo]

@alamb I'm not sure what else I should try and cover in this issue. Can you please help identify what the gap is to closing this issue? Thanks.

[alamb]

Thanks @novemberkilo -- basically I think this is a very common pattern when using Arrow to create arrays via the collect method:

let arr : Int32Array = [Some(1), Some(2)].into_iter().collect();

I am not sure if that is already documented

[novemberkilo]

Roger - will add such to examples 👍🏽

[ByteBaker]

@alamb can we close this probably?