doc: Update

Author: mcmah309

book/src/libs/array/array.md

@@ -1,6 +1,6 @@
 # Array
 ***
-`Arr` (Array) is a zero cost extension type of `List`, where the `List` is treated as non-growable. This is useful for correctly handling lists where growable is false and const lists - as these types of lists are treated the same in the regular Dart type system, which may lead to errors. With `Arr`, type intent is clear for maintainers and developers are able think about code performance more critically.
+[Arr](https://pub.dev/documentation/rust/latest/rust/Arr-extension-type.html) (Array) is a zero cost extension type of `List`, where the `List` is treated as non-growable. This is useful for correctly handling lists where growable is false and const lists - as these types of lists are treated the same in the regular Dart type system, which may lead to errors. With `Arr`, type intent is clear for maintainers and developers are able think about code performance more critically.
 ```dart
 Arr<int?> array = Arr(null, 10);
 ```

book/src/libs/cell/cell.md

@@ -1,14 +1,14 @@
 # Cell
 ***
-Cell is library of useful wrappers types (cells) - [pub.dev](https://pub.dev/documentation/rust/latest/cell/cell-library.html).
+Cell is library of useful wrappers types (cells).
 
-[Cell](#cell) - A wrapper with interior mutability.
+[Cell](https://pub.dev/documentation/rust/latest/rust/Cell-class.html) - A wrapper with interior mutability.
 
-[OnceCell](#oncecell) - A cell which can be written to only once.
+[OnceCell](https://pub.dev/documentation/rust/latest/rust/OnceCell-class.html) - A cell which can be written to only once.
 
-[LazyCell](#lazycell) - A value which is initialized on the first access.
+[LazyCell](https://pub.dev/documentation/rust/latest/rust/LazyCell-class.html) - A value which is initialized on the first access.
 
-[LazyCellAsync](#lazycellasync) - A value which is asynchronously initialized on the first access.
+[LazyCellAsync](https://pub.dev/documentation/rust/latest/rust/LazyCellAsync-class.html) - A value which is asynchronously initialized on the first access.
 
 
 ## Cell

book/src/libs/env/env.md

@@ -1,6 +1,6 @@
 # Env
 
-Env introduces `Env` for handling the environment. It works like `Platform`,
+Env introduces [Env](https://pub.dev/documentation/rust/latest/rust/Env-class.html) for handling the environment. It works like `Platform`,
 except it is cross-platform (also works on web), since it is independent of `dart:io`, and has additional methods.
 
 ```dart

book/src/libs/fs/fs.md

@@ -1,6 +1,8 @@
 # Fs
 
-Fs introduces `Fs`, a container of static methods for working with the file system in a safe manner.
+Fs introduces [Fs](https://pub.dev/documentation/rust/latest/rust/Fs-class.html) and 
+[OpenOptions](https://pub.dev/documentation/rust/latest/rust/OpenOptions-class.html).
+`Fs` is a container of static methods for working with the file system in a safe manner.
 `Fs` combines many of the functionalities in `File`/`Directory`/`Link`/`FileStat`/`FileSystemEntity`
 into one location and will never throw an exception. Instead of using instances of the previous
 entities, `Fs` works only on paths.
@@ -18,4 +20,15 @@ catch (e) {
 // handle
 }
 // handle
+```
+`OpenOptions` is a more extensive builder pattern for opening files in place of `File(..).open(mode)`
+```dart
+OpenOptions options = Options()
+    ..append(true)
+    ..create(true)
+    ..createNew(true)
+    ..read(true)
+    ..truncate(true)
+    ..write(true)
+RandomAccessFile randomAccessFile = options.openSync("path/to/file".asPath()).unwrap();
 ```

book/src/libs/iter/iter.md

@@ -1,7 +1,7 @@
 # Iter
 ***
 A Rust `Iterator` is analogous to the union of a Dart `Iterable` and `Iterator`. Since Dart already has an `Iterator` class, to avoid confusion,
-the Dart implementation of the Rust iterator is `Iter`. `Iter`
+the Dart implementation of the Rust iterator is [Iter](https://pub.dev/documentation/rust/latest/rust/Iter-class.html). `Iter`
 makes working with collections of `rust` types and regular Dart types a breeze. e.g.
 
 ```dart

book/src/libs/ops/ops.md

@@ -4,7 +4,7 @@
 
 ## RangeBounds
 
-`RangeBounds` works the same as Rust's `RangeBounds` (usually seen as syntactic sugar e.g. `1..=3`) 
+[RangeBounds](https://pub.dev/documentation/rust/latest/rust/RangeBounds-class.html) works the same as Rust's `RangeBounds` (usually seen as syntactic sugar e.g. `1..=3`) 
 They have two uses:
 1. `RangeBounds` can be used to get a `Slice` of an `Arr`, `Slice`, or `List`.
 ```dart

book/src/libs/option/option.md

@@ -1,6 +1,6 @@
 # Option
 ***
-`Option` represents the union of two types - `Some<T>` and `None`.
+[Option](https://pub.dev/documentation/rust/latest/rust/Option-class.html) represents the union of two types - `Some<T>` and `None`.
 
 `Option` is easy to declare and translate back and forth between nullable types.
 ```dart

book/src/libs/panic/panic.md

@@ -1,6 +1,6 @@
 # Panic
 ***
-As with `Error` in Dart Core, `Panic` represents a state that should never happen and thus should never be caught.
+As with `Error` in Dart Core, [Panic](https://pub.dev/documentation/rust/latest/rust/Panic-class.html) represents a state that should never happen and thus should never be caught.
 Rust vs Dart Error handling terminology:
 
 | Dart Exception Type | Equivalent in Rust |

book/src/libs/result/result.md

@@ -1,6 +1,6 @@
 # Result
 ***
-`Result<T, E>` is the type used for returning and propagating errors. It is an alternative to throwing exceptions. It is a sealed type with the variants, `Ok(T)`, representing success and containing a value, and `Err(E)`, representing error and containing an error value.
+[Result<T, E>](https://pub.dev/documentation/rust/latest/rust/Result-class.html) is the type used for returning and propagating errors. It is an alternative to throwing exceptions. It is a sealed type with the variants, `Ok(T)`, representing success and containing a value, and `Err(E)`, representing error and containing an error value.
 
 To better understand the motivation around the `Result` type refer to this [article](https://mcmah309.github.io/#/blog/the_result_type_in_dart).
 

book/src/libs/slice/slice.md

@@ -1,6 +1,6 @@
 # Slice
 ***
-A `Slice` is a contiguous sequence of elements in a `List`. Slices are a view into a list without allocating and copying to a new list,
+A [Slice](https://pub.dev/documentation/rust/latest/rust/Slice-class.html) is a contiguous sequence of elements in a `List`. Slices are a view into a list without allocating and copying to a new list,
 thus slices are more efficient than creating a sub-list, but they do not own their own data. That means shrinking the original list can cause the slices range to become invalid, which may cause an exception.
 
 `Slice` also has a lot of efficient methods for in-place mutation within and between slices. e.g.