Taking the Color Out

Sometimes you need the plain text. Log files, display-width calculations, piping to tools that see ANSI sequences as noise: stripping color is a real use case, and Farben covers it.

Farben provides three macros for three different stripping needs. All of them accept format!-style arguments.

unansi! - Strip ANSI Escape Sequences

Removes all CSI ANSI escape sequences from a formatted string. Every sequence of the form ESC [ ... <letter> is removed. Non-CSI ESC bytes are left intact.

use farben::prelude::*;

let colored = "\x1b[31mError\x1b[0m";
let plain = unansi!("{}", colored);
assert_eq!(plain, "Error");

// format args work exactly as you'd expect
let code = 42;
let plain = unansi!("\x1b[1mcode {code}\x1b[0m");
assert_eq!(plain, "code 42");

The return type is String. No extra imports, no intermediate variables.

unmarkup! - Strip Farben Markup Tags

Removes all Farben markup tags (like [bold] or [/]) from a formatted string. Invalid markup is left as-is without panicking.

use farben::prelude::*;

let stripped = unmarkup!("[bold red]Just the text");
assert_eq!("Just the text", stripped);

let invalid = unmarkup!("[I'm unclosed");
assert_eq!("[I'm unclosed", invalid);

// format args work too
let msg = "hey!";
let formatted = unmarkup!("[bold red]{msg}");
assert_eq!("hey!", formatted);

untag! - Escape Markup Brackets

Doubles every [ and ] character so the result contains no parseable tags. Useful when you want to display markup as literal text.

use farben::prelude::*;

let safe = untag!("[bold]hello[/]");
assert_eq!(safe, "[[bold]]hello[[/]]");

let name = "world";
let safe = untag!("[bold]{name}[/]");
assert_eq!(safe, "[[bold]]world[[/]]");

Low-Level Functions

All three macros delegate to functions in farben_core::strip:

• strip_ansi(input: &str) -> String — strips CSI sequences
• strip_markup(input: &str) -> String — strips Farben markup tags
• escape_tags(input: &str) -> String — escapes brackets

use farben_core::strip::strip_ansi;

let colored = "\x1b[31mred text\x1b[0m";
assert_eq!(strip_ansi(colored), "red text");

What Gets Stripped

strip_ansi targets CSI sequences specifically: ESC [ <params> <letter> (the sequences responsible for colors, bold, underline, and other SGR attributes). Things like \x1b[31m, \x1b[0m, \x1b[1;4m.

Bare ESC bytes not followed by [ are passed through unchanged:

use farben_core::strip::strip_ansi;

let bare_esc = "\x1bhello";
assert_eq!(strip_ansi(bare_esc), "\x1bhello");

INFO

This is intentional. Non-CSI escape sequences serve other purposes (terminal mode switching, cursor movement outside of CSI, etc.). Stripping them blindly would corrupt output that uses those sequences legitimately.

When to Strip

A few situations where this comes up:

• Log files. Your terminal output looks great colored, but writing those bytes to a file produces unreadable noise for anything reading it back as plain text.
• Display width. ANSI sequences contribute zero visible characters but real byte count. Strip first, then measure with something like unicode-width.
• Interop. Feeding colored output to a tool (grep, awk, a Slack webhook, a CI log parser) that doesn't know about ANSI.

use farben::prelude::*;
use std::fs::OpenOptions;
use std::io::Write;

let message = cformat!("[red]error:[/] file not found.");

// print in color to the terminal
cprintln!("[red]error:[/] file not found.");

// write plain to the log
let plain = unansi!("{}", message);
let mut log = OpenOptions::new().append(true).open("app.log")?;
writeln!(log, "{plain}")?;

Deprecated Aliases

The macros ansi_strip! and markup_strip! are deprecated in favor of unansi! and unmarkup! respectively. They still work but will be removed in a future release.

Old Name	New Name
ansi_strip!	unansi!
markup_strip!	unmarkup!