diff --git a/TODO/_current.md b/TODO/_current.md
index 3e4a2a7cf..2b02c095d 100644
--- a/TODO/_current.md
+++ b/TODO/_current.md
@@ -66,6 +66,7 @@ TextInput! {
 
 * Text Shaping.
     - Mostly decoupled, needs l10n's Lang.
+        - Can use underlying type LanguageIdentifier?
 
 * Focus.
     - Needs app API.
diff --git a/zero-ui-task/Cargo.toml b/zero-ui-task/Cargo.toml
index 6c4bd308b..407d61c75 100644
--- a/zero-ui-task/Cargo.toml
+++ b/zero-ui-task/Cargo.toml
@@ -6,7 +6,7 @@ edition = "2021"
 license = "Apache-2.0"
 
 [features]
-# 
+# Enables parking_lot deadlock detection.
 deadlock_detection = ["parking_lot/deadlock_detection"]
 
 # Enables http tasks.
@@ -26,6 +26,9 @@ http = [
     "remove_dir_all",
 ]
 
+# Enabled by doc tests.
+test_util = []
+
 [dependencies]
 zero-ui-task-proc-macros = { path = "../zero-ui-task-proc-macros" }
 zero-ui-clone_move = { path = "../zero-ui-clone_move" }
diff --git a/zero-ui-task/src/channel.rs b/zero-ui-task/src/channel.rs
index b742508d6..912a57b5a 100644
--- a/zero-ui-task/src/channel.rs
+++ b/zero-ui-task/src/channel.rs
@@ -8,7 +8,8 @@
 //! # Examples
 //!
 //! ```no_run
-//! use zero_ui_core::{task::{self, channel}, units::*};
+//! use zero_ui_task::{self as task, channel};
+//! # use zero_ui_units::*;
 //!
 //! let (sender, receiver) = channel::bounded(5);
 //!
@@ -257,7 +258,8 @@ impl<T> Receiver<T> {
 /// rapidly consumes all messages in the buffer and new messages as they are send.
 ///
 /// ```no_run
-/// use zero_ui_core::{task::{self, channel}, units::*};
+/// use zero_ui_task::{self as task, channel};
+/// # use zero_ui_units::*;
 ///
 /// let (sender, receiver) = channel::unbounded();
 ///
@@ -306,7 +308,8 @@ pub fn unbounded<T>() -> (UnboundSender<T>, Receiver<T>) {
 /// rapidly consumes the 2 messages in the buffer and unblocks the sender to send more messages.
 ///
 /// ```no_run
-/// use zero_ui_core::{task::{self, channel}, units::*};
+/// use zero_ui_task::{self as task, channel};
+/// # use zero_ui_units::*;
 ///
 /// let (sender, receiver) = channel::bounded(2);
 ///
@@ -352,8 +355,9 @@ pub fn bounded<T>(capacity: usize) -> (Sender<T>, Receiver<T>) {
 /// receiver takes 2 seconds to receive, so the sender takes 2 seconds to send.
 ///
 /// ```no_run
-/// use zero_ui_core::{task::{self, channel}, units::*};
-/// use std::time::*;
+/// use zero_ui_task::{self as task, channel};
+/// # use zero_ui_units::*;
+/// # use std::time::*;
 ///
 /// let (sender, receiver) = channel::rendezvous();
 ///
diff --git a/zero-ui-task/src/http.rs b/zero-ui-task/src/http.rs
index 50aa537d1..1779b3715 100644
--- a/zero-ui-task/src/http.rs
+++ b/zero-ui-task/src/http.rs
@@ -12,7 +12,7 @@
 //! Get some text:
 //!
 //! ```
-//! # use zero_ui_core::task;
+//! # use zero_ui_task as task;
 //! # async fn demo() -> Result<(), Box<dyn std::error::Error>> {
 //! let text = task::http::get_text("https://httpbin.org/base64/SGVsbG8gV29ybGQ=").await?;
 //! println!("{text}!");
@@ -152,7 +152,7 @@ impl Request {
     /// # Examples
     ///
     /// ```
-    /// use zero_ui_core::task::http;
+    /// use zero_ui_task::http;
     ///
     /// # fn try_example() -> Result<(), Box<dyn std::error::Error>> {
     /// let request = http::Request::builder().method(http::Method::PUT)?.uri("https://httpbin.org/put")?.build();
@@ -173,7 +173,7 @@ impl Request {
     /// # Examples
     ///
     /// ```
-    /// use zero_ui_core::task::http;
+    /// use zero_ui_task::http;
     ///
     /// # fn try_example() -> Result<(), Box<dyn std::error::Error>> {
     /// let get = http::Request::get("https://httpbin.org/get")?.build();
@@ -188,7 +188,7 @@ impl Request {
     /// # Examples
     ///
     /// ```
-    /// use zero_ui_core::task::http;
+    /// use zero_ui_task::http;
     ///
     /// # fn try_example() -> Result<(), Box<dyn std::error::Error>> {
     /// let put = http::Request::put("https://httpbin.org/put")?.header("accept", "application/json")?.build();
@@ -203,7 +203,7 @@ impl Request {
     /// # Examples
     ///
     /// ```
-    /// use zero_ui_core::task::http;
+    /// use zero_ui_task::http;
     ///
     /// # fn try_example() -> Result<(), Box<dyn std::error::Error>> {
     /// let post = http::Request::post("https://httpbin.org/post")?.header("accept", "application/json")?.build();
@@ -218,7 +218,7 @@ impl Request {
     /// # Examples
     ///
     /// ```
-    /// use zero_ui_core::task::http;
+    /// use zero_ui_task::http;
     ///
     /// # fn try_example() -> Result<(), Box<dyn std::error::Error>> {
     /// let delete = http::Request::delete("https://httpbin.org/delete")?.header("accept", "application/json")?.build();
@@ -233,7 +233,7 @@ impl Request {
     /// # Examples
     ///
     /// ```
-    /// use zero_ui_core::task::http;
+    /// use zero_ui_task::http;
     ///
     /// # fn try_example() -> Result<(), Box<dyn std::error::Error>> {
     /// let patch = http::Request::patch("https://httpbin.org/patch")?.header("accept", "application/json")?.build();
@@ -248,7 +248,7 @@ impl Request {
     /// # Examples
     ///
     /// ```
-    /// use zero_ui_core::task::http;
+    /// use zero_ui_task::http;
     ///
     /// # fn try_example() -> Result<(), Box<dyn std::error::Error>> {
     /// let head = http::Request::head("https://httpbin.org")?.build();
@@ -1473,7 +1473,7 @@ impl From<isahc::HttpClient> for Client {
 /// # Examples
 ///
 /// ```
-/// use zero_ui_core::task::http::*;
+/// use zero_ui_task::http::*;
 ///
 /// let client = Client::builder().metrics(true).build();
 /// ```
diff --git a/zero-ui-task/src/lib.rs b/zero-ui-task/src/lib.rs
index 22596badf..8a5a21b46 100644
--- a/zero-ui-task/src/lib.rs
+++ b/zero-ui-task/src/lib.rs
@@ -63,7 +63,7 @@
 //! so we recommend blob importing [`io`] to start implementing async IO.
 //!
 //! ```
-//! use zero_ui_core::task::{io::*, fs, rayon::prelude::*};
+//! use zero_ui_task::{io::*, fs, rayon::prelude::*};
 //!
 //! async fn read_numbers() -> Vec<usize> {
 //!     let mut file = fs::File::open("numbers.txt").await.unwrap();
@@ -198,7 +198,8 @@ pub use rayon_ctx::*;
 /// # Examples
 ///
 /// ```
-/// # use zero_ui_core::{task::{self, rayon::iter::*}, var::{ResponseVar, response_var}};
+/// # use zero_ui_task::{self as task, *, rayon::iter::*};
+/// # use zero_ui_var::*;
 /// # struct SomeStruct { sum_response: ResponseVar<usize> }
 /// # impl SomeStruct {
 /// fn on_event(&mut self) {
@@ -463,7 +464,7 @@ impl<'a, 'scope: 'a> ScopeCtx<'a, 'scope> {
 /// # Examples
 ///
 /// ```
-/// # use zero_ui_core::{task::{self, rayon::iter::*}};
+/// # use zero_ui_task::{self as task, rayon::iter::*};
 /// # struct SomeStruct { sum: usize }
 /// # async fn read_numbers() -> Vec<usize> { vec![] }
 /// # impl SomeStruct {
@@ -593,7 +594,8 @@ where
 /// # Examples
 ///
 /// ```
-/// # use zero_ui_core::{task::{self, rayon::iter::*}, var::ResponseVar};
+/// # use zero_ui_task::{self as task, rayon::iter::*};
+/// # use zero_ui_var::*;
 /// # struct SomeStruct { sum_response: ResponseVar<usize> }
 /// # async fn read_numbers() -> Vec<usize> { vec![] }
 /// # impl SomeStruct {
@@ -684,7 +686,7 @@ where
 ///
 /// ```
 /// # fn main() { }
-/// # use zero_ui_core::task;
+/// # use zero_ui_task as task;
 /// # async fn example() {
 /// task::wait(|| std::fs::read_to_string("file.txt")).await
 /// # ; }
@@ -790,8 +792,8 @@ where
 /// Test a [`run`] call:
 ///
 /// ```
-/// use zero_ui_core::task;
-/// # use zero_ui_core::units::*;
+/// use zero_ui_task as task;
+/// # use zero_ui_units::*;
 /// # async fn foo(u: u8) -> Result<u8, ()> { task::deadline(1.ms()).await; Ok(u) }
 ///
 /// #[test]
@@ -918,7 +920,8 @@ pub async fn yield_now() {
 /// Await 5 seconds in a [`spawn`] parallel task:
 ///
 /// ```
-/// use zero_ui_core::{task, units::*};
+/// use zero_ui_task as task;
+/// use zero_ui_units::*;
 ///
 /// task::spawn(async {
 ///     println!("waiting 5 seconds..");
@@ -951,7 +954,7 @@ pub async fn deadline(deadline: impl Into<Deadline>) {
 /// A future that is ready with a closure returns `Some(R)`.
 ///
 /// ```
-/// use zero_ui_core::task;
+/// use zero_ui_task as task;
 /// use std::task::Poll;
 ///
 /// async fn ready_some<R>(mut closure: impl FnMut() -> Option<R>) -> R {
@@ -1015,7 +1018,7 @@ pub async fn with_deadline<O, F: Future<Output = O>>(fut: F, deadline: impl Into
 /// Await for three different futures to complete:
 ///
 /// ```
-/// use zero_ui_core::task;
+/// use zero_ui_task as task;
 ///
 /// # task::doc_test(false, async {
 /// let (a, b, c) = task::all!(
@@ -1148,7 +1151,8 @@ macro_rules! __all {
 /// Await for the first of three futures to complete:
 ///
 /// ```
-/// use zero_ui_core::{task, units::*};
+/// use zero_ui_task as task;
+/// use zero_ui_units::*;
 ///
 /// # task::doc_test(false, async {
 /// let r = task::any!(
@@ -1276,7 +1280,7 @@ pub use zero_ui_task_proc_macros::task_any_all as __proc_any_all;
 /// Await for the first of three futures to complete with `Ok`:
 ///
 /// ```
-/// use zero_ui_core::task;
+/// use zero_ui_task as task;
 /// # #[derive(Debug, PartialEq)]
 /// # pub struct FooError;
 /// # task::doc_test(false, async {
@@ -1421,7 +1425,7 @@ macro_rules! __any_ok {
 /// Await for the first of three futures to complete with `Some`:
 ///
 /// ```
-/// use zero_ui_core::task;
+/// use zero_ui_task as task;
 /// # task::doc_test(false, async {
 /// let r = task::any_some!(
 ///     task::run(async { None::<char> }),
@@ -1559,7 +1563,7 @@ macro_rules! __any_some {
 /// Await for the first of three futures to complete with `Ok(T)`:
 ///
 /// ```
-/// use zero_ui_core::task;
+/// use zero_ui_task as task;
 /// # #[derive(Debug, PartialEq)]
 /// # struct FooError;
 /// # task::doc_test(false, async {
@@ -1576,7 +1580,7 @@ macro_rules! __any_some {
 /// And in if any completes with `Err(E)`:
 ///
 /// ```
-/// use zero_ui_core::task;
+/// use zero_ui_task as task;
 /// # #[derive(Debug, PartialEq)]
 /// # struct FooError;
 /// # task::doc_test(false, async {
@@ -1720,7 +1724,7 @@ macro_rules! __all_ok {
 /// Await for the first of three futures to complete with `Some`:
 ///
 /// ```
-/// use zero_ui_core::task;
+/// use zero_ui_task as task;
 /// # task::doc_test(false, async {
 /// let r = task::all_some!(
 ///     task::run(async { Some('a') }),
@@ -1735,7 +1739,7 @@ macro_rules! __all_ok {
 /// Completes with `None` if any future completes with `None`:
 ///
 /// ```
-/// # use zero_ui_core::task;
+/// # use zero_ui_task as task;
 /// # task::doc_test(false, async {
 /// let r = task::all_some!(
 ///     task::run(async { Some('a') }),
@@ -1864,7 +1868,7 @@ macro_rules! __all_some {
 /// Spawns a parallel task that only writes to stdout after the main thread sets the signal:
 ///
 /// ```
-/// use zero_ui_core::task::{self, *};
+/// use zero_ui_task::{self as task, *};
 ///
 /// let signal = SignalOnce::default();
 ///