1. Your first output

use rich::Console;

fn main() {
    let console = Console::new();
    console.print_str("Hello, world");
    console.print_str("[bold]bold[/], [red]red[/], [bold blue]both[/]");
}

print_str parses console markup — the [tag]…[/] syntax — then applies highlighting and writes the result.

The console adapts to where it is writing

Console::new() inspects the environment once:

It checks	Because
Is stdout a terminal?	If not, styling is dropped — piped output stays clean
How wide is it?	Tables and wrapping need a width; defaults to 80
What colour does it support?	Truecolor, 256, or the basic 16 — colours are downgraded to fit

This is why the following does what you want without any conditionals:

myprogram              # styled, in colour
myprogram > out.txt    # plain text, no escape codes

Printing things that are not strings

print_str is for markup. Anything that implements Renderable — a Table, a Panel, a Markdown document — goes through print:

use rich::{Console, Rule};

let console = Console::new();
console.print(&Rule::new("Section"));

Escaping

A [ only starts a tag when what follows could be one. To be certain a bracket is literal, escape it:

console.print_str("\[not a tag] but [bold]this is[/]");

There is also rich::markup::escape for text you did not write:

let untrusted = "[bold]from a user[/]";
console.print_str(&rich::markup::escape(untrusted));   // prints the tags literally

Escape anything you did not write

Markup is parsed, so user-supplied text containing [ can change your formatting — or fail to parse. Escape it.

Next: Markup and style →