Argv

A lightweight, production-ready command-line argument parser for Dart.

Features

• Flags & Options - Boolean flags and value options with validation
• Commands - Nested command structures (git-like CLIs)
• Validation - Required arguments, allowed values, typo suggestions
• Simple API - Fluent, chainable interface

Quick Start

import 'package:argv/argv.dart';

void main(List<String> args) {
  final parser = Argv('myapp')
    .flag('verbose', abbr: 'v', description: 'Verbose output')
    .option('output', abbr: 'o', defaultValue: 'result.txt')
    .positional('input');

  final result = parser.run(args);
  
  if (result.flag('verbose')) {
    print('Processing ${result.positional('input')}...');
  }
}

Commands

final git = Argv('git');

git.command('commit')
  .option('message', abbr: 'm', required: true)
  .flag('all', abbr: 'a')
  .on((result) {
    print('Committing: ${result.option('message')}');
  });

git.run(['commit', '-m', 'Initial commit', '--all']);

Context

Define multiple on functions for the same command (like a middleware).

void requireName(ArgvResult res) {
    if(res.positional('name') == null) throw Exception('Missing name');
}

final mosaic = Argv('mosaic');

git.command('enable').on(requireName).on(...do something);
git.command('disable').on(requireName);

You can also build the context and access it from every on callback

void requireName(ArgvResult res) {
    if(res.positional('name') == null) throw Exception('Missing name');
}

Future<void> register(ArgvResult res) async {
    final ctx = await Context.load();
    res.set(ctx);
}

final mosaic = Argv('mosaic');

git.command('enable').on(requireName).on(register).on((res) {
    final ctx = res.get<Context>();
    ... use your ctx here
});

Installation

dependencies:
  argv: ^1.0.0

Usage Examples

# Basic usage
myapp --verbose --output result.txt input.txt

# Commands with options  
git commit -m "Fix bug" --all
docker run -d --name myapp nginx:latest

# Validation with suggestions
myapp --verbos  # Error: Unknown argument --verbos. Did you mean --verbose?