Added body to free::zip

Added body to the code example in the docs for free::zip.
The code body added uses two types to make it obvious how `zip`
functions.

Author: JoelMon

src/free.rs

@@ -10,30 +10,24 @@ use std::iter::{self, Zip};
 type VecIntoIter<T> = alloc::vec::IntoIter<T>;
 
 #[cfg(feature = "use_alloc")]
-use alloc::{
-    string::String,
-};
+use alloc::string::String;
 
-use crate::Itertools;
 use crate::intersperse::{Intersperse, IntersperseWith};
+use crate::Itertools;
 
-pub use crate::adaptors::{
-    interleave,
-    merge,
-    put_back,
-};
+pub use crate::adaptors::{interleave, merge, put_back};
 #[cfg(feature = "use_alloc")]
-pub use crate::put_back_n_impl::put_back_n;
+pub use crate::kmerge_impl::kmerge;
+pub use crate::merge_join::merge_join_by;
 #[cfg(feature = "use_alloc")]
 pub use crate::multipeek_impl::multipeek;
 #[cfg(feature = "use_alloc")]
 pub use crate::peek_nth::peek_nth;
 #[cfg(feature = "use_alloc")]
-pub use crate::kmerge_impl::kmerge;
-pub use crate::zip_eq_impl::zip_eq;
-pub use crate::merge_join::merge_join_by;
+pub use crate::put_back_n_impl::put_back_n;
 #[cfg(feature = "use_alloc")]
 pub use crate::rciter_impl::rciter;
+pub use crate::zip_eq_impl::zip_eq;
 
 /// Iterate `iterable` with a particular value inserted between each element.
 ///
@@ -45,8 +39,9 @@ pub use crate::rciter_impl::rciter;
 /// itertools::assert_equal(intersperse((0..3), 8), vec![0, 8, 1, 8, 2]);
 /// ```
 pub fn intersperse<I>(iterable: I, element: I::Item) -> Intersperse<I::IntoIter>
-    where I: IntoIterator,
-          <I as IntoIterator>::Item: Clone
+where
+    I: IntoIterator,
+    <I as IntoIterator>::Item: Clone,
 {
     Itertools::intersperse(iterable.into_iter(), element)
 }
@@ -64,8 +59,9 @@ pub fn intersperse<I>(iterable: I, element: I::Item) -> Intersperse<I::IntoIter>
 /// assert_eq!(i, 8);
 /// ```
 pub fn intersperse_with<I, F>(iterable: I, element: F) -> IntersperseWith<I::IntoIter, F>
-    where I: IntoIterator,
-          F: FnMut() -> I::Item
+where
+    I: IntoIterator,
+    F: FnMut() -> I::Item,
 {
     Itertools::intersperse_with(iterable.into_iter(), element)
 }
@@ -82,7 +78,8 @@ pub fn intersperse_with<I, F>(iterable: I, element: F) -> IntersperseWith<I::Int
 /// }
 /// ```
 pub fn enumerate<I>(iterable: I) -> iter::Enumerate<I::IntoIter>
-    where I: IntoIterator
+where
+    I: IntoIterator,
 {
     iterable.into_iter().enumerate()
 }
@@ -99,8 +96,9 @@ pub fn enumerate<I>(iterable: I) -> iter::Enumerate<I::IntoIter>
 /// }
 /// ```
 pub fn rev<I>(iterable: I) -> iter::Rev<I::IntoIter>
-    where I: IntoIterator,
-          I::IntoIter: DoubleEndedIterator
+where
+    I: IntoIterator,
+    I::IntoIter: DoubleEndedIterator,
 {
     iterable.into_iter().rev()
 }
@@ -112,14 +110,20 @@ pub fn rev<I>(iterable: I) -> iter::Rev<I::IntoIter>
 /// ```
 /// use itertools::zip;
 ///
-/// let data = [1, 2, 3, 4, 5];
-/// for (a, b) in zip(&data, &data[1..]) {
-///     /* loop body */
+/// let data_1 = [1, 2, 3, 4, 5];
+/// let data_2 = ['a', 'b', 'c'];
+/// let mut result: Vec<(i32, char)> = Vec::new();
+///
+/// for (a, b) in zip(&data_1, &data_2) {
+///     result.push((*a, *b));
 /// }
+/// assert_eq!(result, vec![(1, 'a'),(2, 'b'),(3, 'c')]);
 /// ```
+///
 pub fn zip<I, J>(i: I, j: J) -> Zip<I::IntoIter, J::IntoIter>
-    where I: IntoIterator,
-          J: IntoIterator
+where
+    I: IntoIterator,
+    J: IntoIterator,
 {
     i.into_iter().zip(j)
 }
@@ -135,9 +139,13 @@ pub fn zip<I, J>(i: I, j: J) -> Zip<I::IntoIter, J::IntoIter>
 ///     /* loop body */
 /// }
 /// ```
-pub fn chain<I, J>(i: I, j: J) -> iter::Chain<<I as IntoIterator>::IntoIter, <J as IntoIterator>::IntoIter>
-    where I: IntoIterator,
-          J: IntoIterator<Item = I::Item>
+pub fn chain<I, J>(
+    i: I,
+    j: J,
+) -> iter::Chain<<I as IntoIterator>::IntoIter, <J as IntoIterator>::IntoIter>
+where
+    I: IntoIterator,
+    J: IntoIterator<Item = I::Item>,
 {
     i.into_iter().chain(j)
 }
@@ -152,8 +160,9 @@ pub fn chain<I, J>(i: I, j: J) -> iter::Chain<<I as IntoIterator>::IntoIter, <J
 /// assert_eq!(cloned(b"abc").next(), Some(b'a'));
 /// ```
 pub fn cloned<'a, I, T: 'a>(iterable: I) -> iter::Cloned<I::IntoIter>
-    where I: IntoIterator<Item=&'a T>,
-          T: Clone,
+where
+    I: IntoIterator<Item = &'a T>,
+    T: Clone,
 {
     iterable.into_iter().cloned()
 }
@@ -168,8 +177,9 @@ pub fn cloned<'a, I, T: 'a>(iterable: I) -> iter::Cloned<I::IntoIter>
 /// assert_eq!(fold(&[1., 2., 3.], 0., |a, &b| f32::max(a, b)), 3.);
 /// ```
 pub fn fold<I, B, F>(iterable: I, init: B, f: F) -> B
-    where I: IntoIterator,
-          F: FnMut(B, I::Item) -> B
+where
+    I: IntoIterator,
+    F: FnMut(B, I::Item) -> B,
 {
     iterable.into_iter().fold(init, f)
 }
@@ -184,8 +194,9 @@ pub fn fold<I, B, F>(iterable: I, init: B, f: F) -> B
 /// assert!(all(&[1, 2, 3], |elt| *elt > 0));
 /// ```
 pub fn all<I, F>(iterable: I, f: F) -> bool
-    where I: IntoIterator,
-          F: FnMut(I::Item) -> bool
+where
+    I: IntoIterator,
+    F: FnMut(I::Item) -> bool,
 {
     iterable.into_iter().all(f)
 }
@@ -200,8 +211,9 @@ pub fn all<I, F>(iterable: I, f: F) -> bool
 /// assert!(any(&[0, -1, 2], |elt| *elt > 0));
 /// ```
 pub fn any<I, F>(iterable: I, f: F) -> bool
-    where I: IntoIterator,
-          F: FnMut(I::Item) -> bool
+where
+    I: IntoIterator,
+    F: FnMut(I::Item) -> bool,
 {
     iterable.into_iter().any(f)
 }
@@ -216,8 +228,9 @@ pub fn any<I, F>(iterable: I, f: F) -> bool
 /// assert_eq!(max(0..10), Some(9));
 /// ```
 pub fn max<I>(iterable: I) -> Option<I::Item>
-    where I: IntoIterator,
-          I::Item: Ord
+where
+    I: IntoIterator,
+    I::Item: Ord,
 {
     iterable.into_iter().max()
 }
@@ -232,13 +245,13 @@ pub fn max<I>(iterable: I) -> Option<I::Item>
 /// assert_eq!(min(0..10), Some(0));
 /// ```
 pub fn min<I>(iterable: I) -> Option<I::Item>
-    where I: IntoIterator,
-          I::Item: Ord
+where
+    I: IntoIterator,
+    I::Item: Ord,
 {
     iterable.into_iter().min()
 }
 
-
 /// Combine all iterator elements into one String, separated by `sep`.
 ///
 /// [`IntoIterator`] enabled version of [`Itertools::join`].
@@ -250,8 +263,9 @@ pub fn min<I>(iterable: I) -> Option<I::Item>
 /// ```
 #[cfg(feature = "use_alloc")]
 pub fn join<I>(iterable: I, sep: &str) -> String
-    where I: IntoIterator,
-          I::Item: Display
+where
+    I: IntoIterator,
+    I::Item: Display,
 {
     iterable.into_iter().join(sep)
 }
@@ -268,9 +282,9 @@ pub fn join<I>(iterable: I, sep: &str) -> String
 /// ```
 #[cfg(feature = "use_alloc")]
 pub fn sorted<I>(iterable: I) -> VecIntoIter<I::Item>
-    where I: IntoIterator,
-          I::Item: Ord
+where
+    I: IntoIterator,
+    I::Item: Ord,
 {
     iterable.into_iter().sorted()
 }
-