2.4 compatibility in Nexa 3.0

This page describes the retained 2.4 language/runtime path. Sources without a version declaration use this path. Start new Open Programs with Nexa 3.0; compare contracts in the migration guide.

Terminal UI

std.ui provides Markdown, code blocks, panels, status messages, and interactive input for Nexa programs. Rendering uses rich; input uses prompt_toolkit.

Installation and complete example

Install the optional dependencies in your Nexa checkout:

uv sync --locked --extra terminal

This complete program compiles and displays messages in a terminal without a model request.

flow main {
    std.ui.banner("Nexa", "Development workspace");
    std.ui.markdown("# Ready\nInspect the source before execution.");
    std.ui.success("Program loaded");
}

Function	Purpose
banner(title, subtitle)	Application heading
markdown(text) / code(code, language)	Formatted text and code
panel(text, title, style)	Grouped panel
thinking(message, duration)	Timed waiting indicator
success / error / warning / info	Status messages
input(prompt)	Interactive input
agent_reply(name, reply) / tool_call(name, args)	Agent and tool information

These names belong to the std.ui namespace. CJK input behavior depends on the terminal environment; test input, backspace, and cancellation on target terminals when releasing an application. Nexa Code's Ink interface is a separate part of the toolchain.

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Source and validation · terminal / stdlib