Ansi Modifier

Introduction

The package provides the class Ansi holding ANSI modifier codes and the String extension methods style and clearStyle for adding, replacing, and removing ANSI modifiers.

Usage

Include ansi_modifier as a dependency in your pubspec.yaml file.

Use the String extension function style to add new modifiers or to replace existing ones. Use the function clearStyle to remove all Ansi modifier from a string.

import 'package:ansi_modifier/src/ansi.dart';

void main(List<String> args) {
  // Create colorized strings.
  print('\nCreate colorized strings:');
  final blue = 'blueberry'.style(Ansi.blue + Ansi.italic);
  final green = 'green apple'.style(Ansi.green);
  final blueGreen = blue +
      ' and ' +
      green.style(
        Ansi.bold,
        method: Replace.none,
      );
  print('$blue, $green, $blueGreen');

  // Modify a previously colorized string.
  print('\nModify previously colorized strings:');

  // Create custom Ansi modifier.
  final customModifier = Ansi.combine({Ansi.yellow, Ansi.bold, Ansi.underline});

  // Replace first modifier:
  final yellowGreen = blueGreen.style(customModifier, method: Replace.first);

  // Replace all modifiers.
  final magenta =
      yellowGreen.style(Ansi.magenta, method: Replace.clearPrevious);

  // Strip all Ansi modifiers.
  print('$yellowGreen, $magenta, ${magenta.clearStyle()}\n');
}

Runnig the program above:

$ dart example/bin/color_example.dart

produces the following output:

Tips and Tricks

• The String extension method style supports different replacement modes that can be adjusted using the optional argument method.

• Ansi codes can be combined using the addition operator Anis.red + Ansi.bold, or by using the factory constructor Ansi.combine.

• Ansi output can be globally disabled by setting Ansi.status = AnsiOutput.disabled or by using the option:

  $ dart --define=isMonochrome=true example/bin/color_example.dart
  
  

Features and bugs

If some Ansi modifiers are missing please file an enhancement request at the issue tracker.