1//! # Welcome to GPUI!
  2//!
  3//! GPUI is a hybrid immediate and retained mode, GPU accelerated, UI framework
  4//! for Rust, designed to support a wide variety of applications.
  5//!
  6//! ## Getting Started
  7//!
  8//! GPUI is still in active development as we work on the Zed code editor and isn't yet on crates.io.
  9//! You'll also need to use the latest version of stable rust. Add the following to your Cargo.toml:
 10//!
 11//! ```
 12//! gpui = { git = "https://github.com/zed-industries/zed" }
 13//! ```
 14//!
 15//! Everything in GPUI starts with an [`App`]. You can create one with [`App::new`], and
 16//! kick off your application by passing a callback to [`App::run`]. Inside this callback,
 17//! you can create a new window with [`AppContext::open_window`], and register your first root
 18//! view. See [gpui.rs](https://www.gpui.rs/) for a complete example.
 19//!
 20//! ## The Big Picture
 21//!
 22//! GPUI offers three different [registers](https://en.wikipedia.org/wiki/Register_(sociolinguistics)) depending on your needs:
 23//!
 24//! - State management and communication with Models. Whenever you need to store application state
 25//!   that communicates between different parts of your application, you'll want to use GPUI's
 26//!   models. Models are owned by GPUI and are only accessible through an owned smart pointer
 27//!   similar to an [`Rc`]. See the [`app::model_context`] module for more information.
 28//!
 29//! - High level, declarative UI with Views. All UI in GPUI starts with a View. A view is simply
 30//!   a model that can be rendered, via the [`Render`] trait. At the start of each frame, GPUI
 31//!   will call this render method on the root view of a given window. Views build a tree of
 32//!   `elements`, lay them out and style them with a tailwind-style API, and then give them to
 33//!   GPUI to turn into pixels. See the [`elements::Div`] element for an all purpose swiss-army
 34//!   knife for UI.
 35//!
 36//! - Low level, imperative UI with Elements. Elements are the building blocks of UI in GPUI, and they
 37//!   provide a nice wrapper around an imperative API that provides as much flexibility and control as
 38//!   you need. Elements have total control over how they and their child elements are rendered and
 39//!   can be used for making efficient views into large lists, implement custom layouting for a code editor,
 40//!   and anything else you can think of. See the [`element`] module for more information.
 41//!
 42//!  Each of these registers has one or more corresponding contexts that can be accessed from all GPUI services.
 43//!  This context is your main interface to GPUI, and is used extensively throughout the framework.
 44//!
 45//! ## Other Resources
 46//!
 47//! In addition to the systems above, GPUI provides a range of smaller services that are useful for building
 48//! complex applications:
 49//!
 50//! - Actions are user-defined structs that are used for converting keystrokes into logical operations in your UI.
 51//!   Use this for implementing keyboard shortcuts, such as cmd-q. See the [`action`] module for more information.
 52//! - Platform services, such as `quit the app` or `open a URL` are available as methods on the [`app::AppContext`].
 53//! - An async executor that is integrated with the platform's event loop. See the [`executor`] module for more information.,
 54//! - The [gpui::test] macro provides a convenient way to write tests for your GPUI applications. Tests also have their
 55//!   own kind of context, a [`TestAppContext`] which provides ways of simulating common platform input. See [`app::test_context`]
 56//!   and [`test`] modules for more details.
 57//!
 58//! Currently, the best way to learn about these APIs is to read the Zed source code, ask us about it at a fireside hack, or drop
 59//! a question in the [Zed Discord](https://discord.gg/U4qhCEhMXP). We're working on improving the documentation, creating more examples,
 60//! and will be publishing more guides to GPUI on our [blog](https://zed.dev/blog).
 61
 62#![deny(missing_docs)]
 63#![allow(clippy::type_complexity)] // Not useful, GPUI makes heavy use of callbacks
 64#![allow(clippy::collapsible_else_if)] // False positives in platform specific code
 65#![allow(unused_mut)] // False positives in platform specific code
 66
 67#[macro_use]
 68mod action;
 69mod app;
 70
 71mod arena;
 72mod assets;
 73mod color;
 74mod element;
 75mod elements;
 76mod executor;
 77mod geometry;
 78mod image_cache;
 79mod input;
 80mod interactive;
 81mod key_dispatch;
 82mod keymap;
 83mod platform;
 84pub mod prelude;
 85mod scene;
 86mod shared_string;
 87mod shared_uri;
 88mod style;
 89mod styled;
 90mod subscription;
 91mod svg_renderer;
 92mod taffy;
 93#[cfg(any(test, feature = "test-support"))]
 94pub mod test;
 95mod text_system;
 96mod util;
 97mod view;
 98mod window;
 99
100/// Do not touch, here be dragons for use by gpui_macros and such.
101#[doc(hidden)]
102pub mod private {
103    pub use linkme;
104    pub use serde;
105    pub use serde_derive;
106    pub use serde_json;
107}
108
109mod seal {
110    /// A mechanism for restricting implementations of a trait to only those in GPUI.
111    /// See: https://predr.ag/blog/definitive-guide-to-sealed-traits-in-rust/
112    pub trait Sealed {}
113}
114
115pub use action::*;
116pub use anyhow::Result;
117pub use app::*;
118pub(crate) use arena::*;
119pub use assets::*;
120pub use color::*;
121pub use ctor::ctor;
122pub use element::*;
123pub use elements::*;
124pub use executor::*;
125pub use geometry::*;
126pub use gpui_macros::{register_action, test, IntoElement, Render};
127use image_cache::*;
128pub use input::*;
129pub use interactive::*;
130use key_dispatch::*;
131pub use keymap::*;
132pub use platform::*;
133pub use refineable::*;
134pub use scene::*;
135use seal::Sealed;
136pub use shared_string::*;
137pub use shared_uri::*;
138pub use smol::Timer;
139pub use style::*;
140pub use styled::*;
141pub use subscription::*;
142use svg_renderer::*;
143pub use taffy::{AvailableSpace, LayoutId};
144#[cfg(any(test, feature = "test-support"))]
145pub use test::*;
146pub use text_system::*;
147pub use util::arc_cow::ArcCow;
148pub use view::*;
149pub use window::*;
150
151use std::{any::Any, borrow::BorrowMut};
152use taffy::TaffyLayoutEngine;
153
154/// The context trait, allows the different contexts in GPUI to be used
155/// interchangeably for certain operations.
156pub trait Context {
157    /// The result type for this context, used for async contexts that
158    /// can't hold a direct reference to the application context.
159    type Result<T>;
160
161    /// Create a new model in the app context.
162    fn new_model<T: 'static>(
163        &mut self,
164        build_model: impl FnOnce(&mut ModelContext<'_, T>) -> T,
165    ) -> Self::Result<Model<T>>;
166
167    /// Update a model in the app context.
168    fn update_model<T, R>(
169        &mut self,
170        handle: &Model<T>,
171        update: impl FnOnce(&mut T, &mut ModelContext<'_, T>) -> R,
172    ) -> Self::Result<R>
173    where
174        T: 'static;
175
176    /// Read a model from the app context.
177    fn read_model<T, R>(
178        &self,
179        handle: &Model<T>,
180        read: impl FnOnce(&T, &AppContext) -> R,
181    ) -> Self::Result<R>
182    where
183        T: 'static;
184
185    /// Update a window for the given handle.
186    fn update_window<T, F>(&mut self, window: AnyWindowHandle, f: F) -> Result<T>
187    where
188        F: FnOnce(AnyView, &mut WindowContext<'_>) -> T;
189
190    /// Read a window off of the application context.
191    fn read_window<T, R>(
192        &self,
193        window: &WindowHandle<T>,
194        read: impl FnOnce(View<T>, &AppContext) -> R,
195    ) -> Result<R>
196    where
197        T: 'static;
198}
199
200/// This trait is used for the different visual contexts in GPUI that
201/// require a window to be present.
202pub trait VisualContext: Context {
203    /// Construct a new view in the window referenced by this context.
204    fn new_view<V>(
205        &mut self,
206        build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
207    ) -> Self::Result<View<V>>
208    where
209        V: 'static + Render;
210
211    /// Update a view with the given callback
212    fn update_view<V: 'static, R>(
213        &mut self,
214        view: &View<V>,
215        update: impl FnOnce(&mut V, &mut ViewContext<'_, V>) -> R,
216    ) -> Self::Result<R>;
217
218    /// Replace the root view of a window with a new view.
219    fn replace_root_view<V>(
220        &mut self,
221        build_view: impl FnOnce(&mut ViewContext<'_, V>) -> V,
222    ) -> Self::Result<View<V>>
223    where
224        V: 'static + Render;
225
226    /// Focus a view in the window, if it implements the [`FocusableView`] trait.
227    fn focus_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
228    where
229        V: FocusableView;
230
231    /// Dismiss a view in the window, if it implements the [`ManagedView`] trait.
232    fn dismiss_view<V>(&mut self, view: &View<V>) -> Self::Result<()>
233    where
234        V: ManagedView;
235}
236
237/// A trait that allows models and views to be interchangeable in certain operations
238pub trait Entity<T>: Sealed {
239    /// The weak reference type for this entity.
240    type Weak: 'static;
241
242    /// The ID for this entity
243    fn entity_id(&self) -> EntityId;
244
245    /// Downgrade this entity to a weak reference.
246    fn downgrade(&self) -> Self::Weak;
247
248    /// Upgrade this entity from a weak reference.
249    fn upgrade_from(weak: &Self::Weak) -> Option<Self>
250    where
251        Self: Sized;
252}
253
254/// A trait for tying together the types of a GPUI entity and the events it can
255/// emit.
256pub trait EventEmitter<E: Any>: 'static {}
257
258/// A helper trait for auto-implementing certain methods on contexts that
259/// can be used interchangeably.
260pub trait BorrowAppContext {
261    /// Set a global value on the context.
262    fn set_global<T: Global>(&mut self, global: T);
263}
264
265impl<C> BorrowAppContext for C
266where
267    C: BorrowMut<AppContext>,
268{
269    fn set_global<G: Global>(&mut self, global: G) {
270        self.borrow_mut().set_global(global)
271    }
272}
273
274/// A flatten equivalent for anyhow `Result`s.
275pub trait Flatten<T> {
276    /// Convert this type into a simple `Result<T>`.
277    fn flatten(self) -> Result<T>;
278}
279
280impl<T> Flatten<T> for Result<Result<T>> {
281    fn flatten(self) -> Result<T> {
282        self?
283    }
284}
285
286impl<T> Flatten<T> for Result<T> {
287    fn flatten(self) -> Result<T> {
288        self
289    }
290}
291
292/// A marker trait for types that can be stored in GPUI's global state.
293///
294/// Implement this on types you want to store in the context as a global.
295pub trait Global: 'static {}