colored_text

A simple and intuitive library for adding colors and styles to terminal text in Rust.

Features

• Simple method-call syntax for applying colors and styles
• Support for basic colors, bright colors, and background colors
• Text styling (bold, dim, italic, underline, inverse, strikethrough)
• RGB and HEX color support for both text and background
• Composed style chaining with predictable override behavior
• Works with string literals, owned strings, and format macros
• Zero dependencies
• Supports the NO_COLOR environment variable - if this is set, all colors are disabled and the text is returned uncolored
• Supports explicit runtime color modes: Auto, Always, and Never
• Detects if the output is NOT going to a terminal (e.g. is going to a file or a pipe) and disables colors in Auto mode
• Supports explicit target-aware rendering for stdout, stderr, or custom terminal-aware destinations
• Complete documentation and examples

Installation

Add this to your Cargo.toml:

[dependencies]
colored_text = "0.4.1"

Usage

use colored_text::Colorize;

// Basic colors
println!("{}", "Red text".red());
println!("{}", "Blue text".blue());
println!("{}", "Green text".green());

// Background colors
println!("{}", "Red background".on_red());
println!("{}", "Blue background".on_blue());

// Text styles
println!("{}", "Bold text".bold());
println!("{}", "Italic text".italic());
println!("{}", "Underlined text".underline());

// RGB and Hex colors
println!("{}", "Custom color".rgb(255, 128, 0));
println!("{}", "Custom background".on_rgb(0, 128, 255));
println!("{}", "Hex color".hex("#ff8000"));
println!("{}", "Hex background".on_hex("#0080ff"));

// Chaining styles
println!("{}", "Bold red text".red().bold());
println!("{}", "Italic blue on yellow".blue().italic().on_yellow());

// Using with format! macro
let name = "World";
println!("Hello, {}!", name.blue().bold());

// Removing all styles
println!("{}", "Back to plain text".red().bold().clear());

Available Methods

Colors

• .red()
• .green()
• .blue()
• .yellow()
• .magenta()
• .cyan()
• .white()
• .black()

Bright Colors

• .bright_red()
• .bright_green()
• .bright_blue()
• .bright_yellow()
• .bright_magenta()
• .bright_cyan()
• .bright_white()

Background Colors

• .on_red()
• .on_green()
• .on_blue()
• .on_yellow()
• .on_magenta()
• .on_cyan()
• .on_white()
• .on_black()

Styles

• .bold()
• .dim()
• .italic()
• .underline()
• .inverse() - Swap foreground and background colors
• .strikethrough() - Draw a line through the text

RGB, HSL, and Hex Colors

• .rgb(r, g, b) - Custom text color using RGB values (0-255, compile-time enforced)
• .on_rgb(r, g, b) - Custom background color using RGB values (0-255, compile-time enforced)
• .hsl(h, s, l) - Custom text color using HSL values (hue: 0-360°, saturation: 0-100%, lightness: 0-100%)
• .on_hsl(h, s, l) - Custom background color using HSL values
• .hex(code) - Custom text color using HTML/CSS hex code (e.g., "#ff8000" or "ff8000")
• .on_hex(code) - Custom background color using HTML/CSS hex code

Other

• .clear() - Remove all styling

Input Handling and Validation

• RGB values must be in range 0-255 (enforced at compile time via u8 type)
• Attempting to use RGB values > 255 will result in a compile error
• Hex color codes can be provided with or without the '#' prefix in either 3-character shorthand or 6-character full form
• Invalid hex codes (wrong length, invalid characters) will result in plain unstyled text
• All color methods are guaranteed to return a valid string, never panicking

// RGB values are constrained to 0-255
println!("{}", "RGB color".rgb(255, 128, 0));

// HSL values (hue: 0-360°, saturation/lightness: 0-100%)
println!("{}", "Red".hsl(0.0, 100.0, 50.0));     // Pure red
println!("{}", "Green".hsl(120.0, 100.0, 50.0)); // Pure green
println!("{}", "Blue".hsl(240.0, 100.0, 50.0));  // Pure blue
println!("{}", "Gray".hsl(0.0, 0.0, 50.0));      // 50% gray

// Hex colors work with or without #
println!("{}", "Hex color".hex("#ff8000"));
println!("{}", "Also valid".hex("ff8000"));
println!("{}", "Shorthand".hex("#f80"));

// Invalid hex codes return uncolored text
println!("{}", "Invalid".hex("xyz")); // Returns uncolored text
println!("{}", "Wrong length".hex("#1234")); // Returns uncolored text

NO_COLOR Support

This library respects the NO_COLOR environment variable. If NO_COLOR is set (to any value), all color and style methods will return plain unformatted text. This makes it easy to disable all colors globally if needed.

// Colors enabled (NO_COLOR not set)
println!("{}", "Red text".red()); // Prints in red

// With NO_COLOR set
std::env::set_var("NO_COLOR", "1");
println!("{}", "Red text".red()); // Prints without color

Runtime Color Modes

By default, this library uses ColorMode::Auto: it checks if stdout is going to a terminal and disables colors when it is not. Applications can override that behavior explicitly using ColorizeConfig:

use colored_text::{ColorMode, Colorize, ColorizeConfig};

ColorizeConfig::set_color_mode(ColorMode::Always);
println!("{}", "Always colored".red());

ColorizeConfig::set_color_mode(ColorMode::Never);
println!("{}", "Never colored".red());

ColorizeConfig::set_color_mode(ColorMode::Auto);
println!("{}", "Colored only in terminals".red());

The runtime configuration is thread-local. This is useful in tests or applications that want to force color on or off for a specific execution path.

NO_COLOR still takes precedence in Auto and Always mode. If NO_COLOR is set, output is plain text.

For non-stdout destinations, use StyledText::render with a RenderTarget so Auto mode evaluates the real output target:

use colored_text::{Colorize, RenderTarget};

let warning = "Warning".yellow().bold();

eprintln!("{}", warning.render(RenderTarget::Stderr));

let captured = warning.render(RenderTarget::Terminal(false));
assert_eq!(captured, "Warning");

Terminal Compatibility

This library uses ANSI escape codes for coloring and styling text. Most modern terminals support these codes, but the actual appearance may vary depending on your terminal emulator and its configuration:

• Basic colors (codes 30-37) are widely supported
• Bright colors (codes 90-97) may appear the same as basic colors in some terminals
• RGB colors require true color support in your terminal
• Some styling options (like italic) might not work in all terminals

Examples

Check out the examples directory for more usage examples.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.