A Dart library for building console applications.

pub package Language

This library contains a variety of useful functions for console application development, including:

  • Reading the current window dimensions (height, width)
  • Reading and setting the cursor location
  • Setting foreground and background colors
  • Manipulating the console into "raw mode", which allows more advanced keyboard input processing than the default dart:io library.
  • Reading keys and control sequences from the keyboard
  • Writing aligned text to the screen

The library has been used to implement a Dart version of the Kilo text editor; when compiled with dart2native that results in a self-contained kilo executable. The library is sufficient for a reasonably complete set of usage, including readline-style CLI and basic text games.

The library assumes a terminal that recognizes and implements common ANSI escape sequences. The package has been tested on macOS, Linux and Windows 10 version 1903. Windows support is preliminary - the library is tested on the Windows Terminal and cmd, but some functions will not work on older versions of Windows that do not support ANSI escape sequences.

The library uses the win32 package for accessing the Win32 API through FFI. That package contains many examples of using Dart FFI for more complex examples.

Usage

A simple example for the dart_console package:

import 'package:dart_console/dart_console.dart';

main() {
  final console = Console();

  console.clearScreen();
  console.resetCursorPosition();

  console.writeLine(
    'Console size is ${console.windowWidth} cols and ${console.windowHeight} rows.',
    TextAlignment.center,
  );

  console.writeLine();

  return 0;
}

More comprehensive demos of the Console class are provided, as follows:

ExampleDescription
demo.dartSuite of test demos that showcase various capabilities
main.dartBasic demo of how to get started with the dart_console
keys.dartDemonstrates how dart_console processes control characters
readline.dartSample command-line interface / REPL
kilo.dartRudimentary text editor
life.dartGame of Life

Acknowledgements

Special thanks to Matt Sullivan (@mjohnsullivan) and Samir Jindel (@sjindel-google) for their help understanding the vagaries of FFI in its early state.

Thanks to @erf for contributing the Game of Life example.

Features and bugs

Please file feature requests and bugs at the issue tracker.

Libraries

dart_console
Console library [...]