Rich is a comprehensive library for building sophisticated command-line interfaces and terminal applications. It provides a robust console formatting engine and a layout framework that enables developers to render rich text, syntax-highlighted code, and complex data structures directly in the terminal. By utilizing a recursive constraint-based layout engine, the library allows for the creation of hierarchical grids, panels, and trees that maintain their structure even as terminal dimensions change.
What distinguishes the library is its ability to manage persistent, real-time terminal interfaces through live display management and buffered stream handling. It offers granular control over output through a protocol-based rendering system, allowing developers to define custom representations for objects and manage complex visual arrangements. The library also includes a specialized diagnostic suite that automatically captures and transforms raw stack traces into human-readable, syntax-highlighted error reports, complete with local variable inspection.
Beyond its core rendering capabilities, the library provides a suite of tools for data visualization and user interaction. This includes support for nested progress tracking, animated status indicators, and interactive input prompts. Developers can apply consistent visual branding across their applications using a centralized markup-based styling system, which supports reusable themes, color palettes, and text attributes for precise alignment and formatting.
The library automatically detects the host terminal environment to ensure compatibility and visual consistency across different systems.
