Made StructIterator and NestedArrayIter public (#1385)

src/io/parquet/read/deserialize/mod.rs

@@ -22,6 +22,7 @@ use crate::{
 };
 
 pub use self::nested_utils::{init_nested, InitNested, NestedArrayIter, NestedState};
+pub use self::struct_::StructIterator;
 use simple::page_iter_to_arrays;
 
 use super::*;

src/io/parquet/read/deserialize/nested_utils.rs

@@ -556,5 +556,6 @@ where
     }
 }
 
+/// Type def for a sharable, boxed dyn [`Iterator`] of NestedStates and arrays
 pub type NestedArrayIter<'a> =
     Box<dyn Iterator<Item = Result<(NestedState, Box<dyn Array>)>> + Send + Sync + 'a>;

src/io/parquet/read/deserialize/struct_.rs

@@ -4,12 +4,14 @@ use crate::error::Error;
 
 use super::nested_utils::{NestedArrayIter, NestedState};
 
+/// An iterator adapter over [`NestedArrayIter`] assumed to be encoded as Struct arrays
 pub struct StructIterator<'a> {
     iters: Vec<NestedArrayIter<'a>>,
     fields: Vec<Field>,
 }
 
 impl<'a> StructIterator<'a> {
+    /// Creates a new [`StructIterator`] with `iters` and `fields`.
     pub fn new(iters: Vec<NestedArrayIter<'a>>, fields: Vec<Field>) -> Self {
         assert_eq!(iters.len(), fields.len());
         Self { iters, fields }

src/io/parquet/read/mod.rs

@@ -36,7 +36,7 @@ use crate::{array::Array, error::Result};
 
 pub use deserialize::{
     column_iter_to_arrays, create_list, get_page_iterator, init_nested, n_columns, InitNested,
-    NestedState,
+    NestedArrayIter, NestedState, StructIterator,
 };
 pub use file::{FileReader, RowGroupReader};
 pub use row_group::*;