Expand description
§Why R3BL?
R3BL TUI library & suite of apps focused on developer productivity
We are working on building command line apps in Rust which have rich text user interfaces (TUI). We want to lean into the terminal as a place of productivity, and build all kinds of awesome apps for it.
-
đź”® Instead of just building one app, we are building a library to enable any kind of rich TUI development w/ a twist: taking concepts that work really well for the frontend mobile and web development world and re-imagining them for TUI & Rust.
- Taking inspiration from things like React, SolidJS, Elm, iced-rs, Jetpack Compose, JSX, CSS, but making everything async (so they can be run in parallel & concurrent via Tokio).
- Even the thread running the main event loop doesn’t block since it is async.
- Using proc macros to create DSLs to implement something inspired by CSS & JSX.
-
🌎 We are building apps to enhance developer productivity & workflows.
- The idea here is not to rebuild
tmuxin Rust (separate processes mux’d onto a single terminal window). Rather it is to build a set of integrated “apps” (or “tasks”) that run in the same process that renders to one terminal window. - Inside of this terminal window, we can implement things like “app” switching, routing, tiling layout, stacking layout, etc. so that we can manage a lot of TUI apps (which are tightly integrated) that are running in the same process, in the same window. So you can imagine that all these “app“s have shared application state. Each “app” may also have its own local application state.
- Here are some examples of the types of “app“s we plan to build (for which this
infrastructure acts as the open source engine):
- Multi user text editors w/ syntax highlighting.
- Integrations w/ github issues.
- Integrations w/ calendar, email, contacts APIs.
- The idea here is not to rebuild
All the crates in the r3bl-open-core
repo provide lots of useful
functionality to help you build TUI (text user interface) apps, along w/ general
niceties & ergonomics that all Rustaceans 🦀 can enjoy 🎉.
§Table of contents
- Introduction
- Changelog
- Learn how these crates are built, provide feedback
- How to use it
- Build, run, test tasks
- References
- Why make a new crate for this?
§Introduction
Rust crate to generate formatted ANSI 256 (8-bit) and truecolor (24-bit) color output to stdout. On macOS, the default Terminal.app does not support truecolor, so ANSI 256 colors are used instead.
This crate performs its own detection of terminal color capability heuristically. And does not use other crates to perform this function.
Here’s a screenshot of running the main example on various operating systems:
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| Running on Linux Tilix |
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| Running on Windows Terminal |
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| Running on macOS terminal app (note ANSI 256 runtime detection) |
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| Running on macOS iTerm app (note Truecolor runtime detection) |
§Changelog
Please check out the changelog to see how the library has evolved over time.
§Learn how these crates are built, provide feedback
To learn how we built this crate, please take a look at the following resources.
- If you like consuming video content, here’s our YT channel. Please consider subscribing.
- If you like consuming written content, here’s our developer site. Please consider subscribing to our newsletter.
- If you have questions, please join our discord server.
§How to use it
The main struct that we have to consider is AnsiStyledText. It has two fields:
text- the text to print.style- a list of styles to apply to the text.
Here’s an example.
use r3bl_ansi_color::{AnsiStyledText, Style, Color};
AnsiStyledText {
text: "Print a formatted (bold, italic, underline) string w/ ANSI color codes.",
style: &[
Style::Bold,
Style::Italic,
Style::Underline,
Style::Foreground(Color::Rgb(50, 50, 50)),
Style::Background(Color::Rgb(100, 200, 1)),
],
}
.println();Please a look at the
main example to get a
better idea of how to use this crate.
§Build, run, test tasks
§Prerequisites
🌠In order for these to work you have to install the Rust toolchain and nu and
cargo-watch:
- Install the Rust toolchain using
rustupby following the instructions here. - Install
cargo-watchusingcargo install cargo-watch. - Install
flamegraphusingcargo install flamegraph. - Install
nuon your system usingcargo install nu. It is available for Linux, macOS, and Windows. And it is written in Rust.
§Nushell commands
| Command | Description |
|---|---|
nu run build | Build the project |
nu run clean | Clean the project |
nu run run | Run examples |
nu run run-release | Run examples with release flag |
nu run run-flamegraph | Run examples with flamegraph profiling |
nu run test | Run tests |
nu run clippy | Run clippy |
nu run docs | Build docs |
nu run serve-docs | Serve docs. Useful if you SSH into a remote machine via VSCode and want to view the docs locally |
nu run upgrade-deps | Upgrade dependencies |
nu run rustfmt | Run rustfmt |
The following commands will watch for changes in the source folder and re-run:
| Command | Description |
|---|---|
nu run watch-run | Watch run |
nu run watch-all-tests | Watch all tests |
nu run watch-one-test <test_name> | Watch one test |
nu run watch-clippy | Watch clippy |
nu run watch-macro-expansion-one-test <test_name> | Watch macro expansion for one test |
§References
- ANSI Escape Codes
- ASCII Table
- Xterm 256color Chart
- 256 Colors Cheat Sheet
- List of ANSI Color Escape Sequences
- Color Metric
§Why make a new crate for this?
- There are a few crates on crates.io that do similar things but they don’t amenable licenses.
- Other crates simply ignore ANSI 256 colors and only support truecolor, even when they claim that they support it.
- And there are other crates which don’t correctly report that macOS Terminal.app does not support truecolor and only supports ANSI 256 color.
Here are some relevant links:
- Issue 47:
concolor anstreamdocumentationcolorchoicedocumentationcolorchoice-clapdocumentationterm_supports_ansi_colorfunctionanstyle-querycratesupports-colordocumentationr3bl_ansi_colorcrate (the source inansi_colorfolder is this crate)coloredcrate
Re-exports§
pub use ansi256_color::*;Deprecated pub use ansi_escape_codes::*;Deprecated pub use ansi_styled_text::*;Deprecated pub use color::*;Deprecated pub use convert::*;Deprecated pub use detect_color_support::*;Deprecated pub use rgb_color::*;Deprecated pub use term::*;Deprecated pub use transform_color::*;Deprecated
Modules§
- ansi256_
color Deprecated - ansi_
escape_ codes Deprecated - More info:
- ansi_
styled_ text Deprecated - color
Deprecated - More info:
- convert
Deprecated - More info:
- detect_
color_ support Deprecated - rgb_
color Deprecated - term
Deprecated - transform_
color Deprecated



