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//! This is a library for controlling colours and formatting, such as
//! red bold text or blue underlined text, on ANSI terminals.
//!
//!
//! ## Basic usage
//!
//! There are two main data structures in this crate that you need to be
//! concerned with: `ANSIString` and `Style`. A `Style` holds stylistic
//! information: colours, whether the text should be bold, or blinking, or
//! whatever. There are also `Colour` variants that represent simple foreground
//! colour styles. An `ANSIString` is a string paired with a `Style`.
//!
//! (Yes, it’s British English, but you won’t have to write “colour” very often.
//! `Style` is used the majority of the time.)
//!
//! To format a string, call the `paint` method on a `Style` or a `Colour`,
//! passing in the string you want to format as the argument. For example,
//! here’s how to get some red text:
//!
//! use ansi_term::Colour::Red;
//! println!("This is in red: {}", Red.paint("a red string"));
//!
//! It’s important to note that the `paint` method does *not* actually return a
//! string with the ANSI control characters surrounding it. Instead, it returns
//! an `ANSIString` value that has a `Display` implementation that, when
//! formatted, returns the characters. This allows strings to be printed with a
//! minimum of `String` allocations being performed behind the scenes.
//!
//! If you *do* want to get at the escape codes, then you can convert the
//! `ANSIString` to a string as you would any other `Display` value:
//!
//! use ansi_term::Colour::Red;
//! use std::string::ToString;
//! let red_string = Red.paint("a red string").to_string();
//!
//!
//! ## Bold, underline, background, and other styles
//!
//! For anything more complex than plain foreground colour changes, you need to
//! construct `Style` objects themselves, rather than beginning with a `Colour`.
//! You can do this by chaining methods based on a new `Style`, created with
//! `Style::new()`. Each method creates a new style that has that specific
//! property set. For example:
//!
//! use ansi_term::Style;
//! println!("How about some {} and {}?",
//! Style::new().bold().paint("bold"),
//! Style::new().underline().paint("underline"));
//!
//! For brevity, these methods have also been implemented for `Colour` values,
//! so you can give your styles a foreground colour without having to begin with
//! an empty `Style` value:
//!
//! use ansi_term::Colour::{Blue, Yellow};
//! println!("Demonstrating {} and {}!",
//! Blue.bold().paint("blue bold"),
//! Yellow.underline().paint("yellow underline"));
//! println!("Yellow on blue: {}", Yellow.on(Blue).paint("wow!"));
//!
//! The complete list of styles you can use are: `bold`, `dimmed`, `italic`,
//! `underline`, `blink`, `reverse`, `hidden`, `strikethrough`, and `on` for
//! background colours.
//!
//! In some cases, you may find it easier to change the foreground on an
//! existing `Style` rather than starting from the appropriate `Colour`.
//! You can do this using the `fg` method:
//!
//! use ansi_term::Style;
//! use ansi_term::Colour::{Blue, Cyan, Yellow};
//! println!("Yellow on blue: {}", Style::new().on(Blue).fg(Yellow).paint("yow!"));
//! println!("Also yellow on blue: {}", Cyan.on(Blue).fg(Yellow).paint("zow!"));
//!
//! Finally, you can turn a `Colour` into a `Style` with the `normal` method.
//! This will produce the exact same `ANSIString` as if you just used the
//! `paint` method on the `Colour` directly, but it’s useful in certain cases:
//! for example, you may have a method that returns `Styles`, and need to
//! represent both the “red bold” and “red, but not bold” styles with values of
//! the same type. The `Style` struct also has a `Default` implementation if you
//! want to have a style with *nothing* set.
//!
//! use ansi_term::Style;
//! use ansi_term::Colour::Red;
//! Red.normal().paint("yet another red string");
//! Style::default().paint("a completely regular string");
//!
//!
//! ## Extended colours
//!
//! You can access the extended range of 256 colours by using the `Fixed` colour
//! variant, which takes an argument of the colour number to use. This can be
//! included wherever you would use a `Colour`:
//!
//! use ansi_term::Colour::Fixed;
//! Fixed(134).paint("A sort of light purple");
//! Fixed(221).on(Fixed(124)).paint("Mustard in the ketchup");
//!
//! The first sixteen of these values are the same as the normal and bold
//! standard colour variants. There’s nothing stopping you from using these as
//! `Fixed` colours instead, but there’s nothing to be gained by doing so
//! either.
//!
//! You can also access full 24-bit color by using the `RGB` colour variant,
//! which takes separate `u8` arguments for red, green, and blue:
//!
//! use ansi_term::Colour::RGB;
//! RGB(70, 130, 180).paint("Steel blue");
//!
//! ## Combining successive coloured strings
//!
//! The benefit of writing ANSI escape codes to the terminal is that they
//! *stack*: you do not need to end every coloured string with a reset code if
//! the text that follows it is of a similar style. For example, if you want to
//! have some blue text followed by some blue bold text, it’s possible to send
//! the ANSI code for blue, followed by the ANSI code for bold, and finishing
//! with a reset code without having to have an extra one between the two
//! strings.
//!
//! This crate can optimise the ANSI codes that get printed in situations like
//! this, making life easier for your terminal renderer. The `ANSIStrings`
//! struct takes a slice of several `ANSIString` values, and will iterate over
//! each of them, printing only the codes for the styles that need to be updated
//! as part of its formatting routine.
//!
//! The following code snippet uses this to enclose a binary number displayed in
//! red bold text inside some red, but not bold, brackets:
//!
//! use ansi_term::Colour::Red;
//! use ansi_term::{ANSIString, ANSIStrings};
//! let some_value = format!("{:b}", 42);
//! let strings: &[ANSIString<'static>] = &[
//! Red.paint("["),
//! Red.bold().paint(some_value),
//! Red.paint("]"),
//! ];
//! println!("Value: {}", ANSIStrings(strings));
//!
//! There are several things to note here. Firstly, the `paint` method can take
//! *either* an owned `String` or a borrowed `&str`. Internally, an `ANSIString`
//! holds a copy-on-write (`Cow`) string value to deal with both owned and
//! borrowed strings at the same time. This is used here to display a `String`,
//! the result of the `format!` call, using the same mechanism as some
//! statically-available `&str` slices. Secondly, that the `ANSIStrings` value
//! works in the same way as its singular counterpart, with a `Display`
//! implementation that only performs the formatting when required.
//!
//! ## Byte strings
//!
//! This library also supports formatting `[u8]` byte strings; this supports
//! applications working with text in an unknown encoding. `Style` and
//! `Color` support painting `[u8]` values, resulting in an `ANSIByteString`.
//! This type does not implement `Display`, as it may not contain UTF-8, but
//! it does provide a method `write_to` to write the result to any
//! `io::Write`:
//!
//! use ansi_term::Colour::Green;
//! Green.paint("user data".as_bytes()).write_to(&mut std::io::stdout()).unwrap();
//!
//! Similarly, the type `ANSIByteStrings` supports writing a list of
//! `ANSIByteString` values with minimal escape sequences:
//!
//! use ansi_term::Colour::Green;
//! use ansi_term::ANSIByteStrings;
//! ANSIByteStrings(&[
//! Green.paint("user data 1\n".as_bytes()),
//! Green.bold().paint("user data 2\n".as_bytes()),
//! ]).write_to(&mut std::io::stdout()).unwrap();
#![crate_name = "ansi_term"]
#![crate_type = "rlib"]
#![crate_type = "dylib"]
#![warn(missing_copy_implementations)]
#![warn(missing_docs)]
#![warn(trivial_casts, trivial_numeric_casts)]
#![warn(unused_extern_crates, unused_qualifications)]
#[cfg(target_os="windows")]
extern crate winapi;
mod ansi;
pub use ansi::{Prefix, Infix, Suffix};
mod style;
pub use style::{Colour, Style};
/// Color is a type alias for Colour for those who can't be bothered.
pub use Colour as Color;
// I'm not beyond calling Colour Colour, rather than Color, but I did
// purposefully name this crate 'ansi-term' so people wouldn't get
// confused when they tried to install it.
//
// Only *after* they'd installed it.
mod difference;
mod display;
pub use display::*;
mod write;
mod windows;
pub use windows::*;
mod debug;