Command Line Argument Manager

This tool is based on https://deno.land/std/flags/mod.ts and provides a straightforward way to declare and parse command line options for a deno program. A help page can be automatically generated and viewed with --help.

Define Command Line Options

// create a CommandLineOptions instance
const options = new CommandLineOptions("Name of the Program/Library", "Describe what this program does");

// declare options and get their values
const customOptionA = options.option("optionA", {type: "boolean", description:"Describe what this option does"})
const customOptionB = options.option("optionB", {type: "string", description:"Describe what this option does", default: "default value"})
const customOptionC = options.option("optionC", {required: true, description:"Describe what this option does"})

Define Custom Commands with Options

const commandOptions = options.command("customCommand", {
    'commandOptionA':  {type:"boolean"},
    'commandOptionB':  {type:"string"}
})

$ deno run example.ts customCommand --commandOptionA --commandOptionB valueB

If the program is now called with the command "customCommand", commandOptions is an object containing the command option values. If the program is called with a different or no command, commandOptions is null.

Generate the help page

The CommandLineOptions.printHelp() method can always be called to print all currently declared command line options.

When using the --help option, this method is also called in the background, and the process is stopped directly afterwards. In this scenario, custom command line options declared during the initialization of the program might not yet be loaded and not shown on the help page.

For this reason, this tool allows you to generate a static help page, RUN.md which serves as a human readable help document, but is also parsed by the command line argument manager to display a help page in the console when using --help.

To generate or update this file, start your program with the --generate-help option. All options that are registered with a CommandLineOptions instance during the runtime of the program will be added to the RUN.md file.