Clad

Clad is a simple command line arguments parser. It is inspired by the awesome rust library, clap.

Features

• Supports short (-f), long (--long) and positional arguments.
• --option value and --option=value are allowed.
• -f value, -f=value and -fvalue are also allowed.
• You can combine short flags: -Syu is the same as -S -y -u.
• You can specify any flag to take multiple values.
• You can specify default values.
• Pass positional values that start with - after --. E.g. ./amyapp -- -somevalue.
• Supports required/optional flags.
• Supports per-argument validation with a closure.
• Simple interface.
• Auto generated help message.

Unsupported

For now there is no support for subcommands.

Import

Make sure to specify an exact version!

import * as clad from "https://deno.land/x/clad/mod.ts";
// Or take what you need:
// import { Command } from "https://deno.land/x/clad/mod.ts";

Usage Example

import { Command } from "https://deno.land/x/clad/mod.ts";

const args = new Command("concat", {
    sep: {
        help: "The separator used to concatenate words",
        default: "-",
        flags: ["s", "sep", "separator"],
    },
    cap: {
        help: "Make each word all caps",
        flags: ["c", "capitalize"],
    },
    words: {
        help: "Any number of words to join",
        multi: true,
        required: true,
    },
})
    .about("Concatenate words with a separator")
    .parse(Deno.args);

const mapper = (s: string): string => args.cap ? s.toUpperCase() : s;
console.log((args.words as string[]).map(mapper).join(args.sep as string));

Example Output

$ deno run ./concat.ts -h
USAGE: concat [OPTIONS] ARGS...
Concatenate words with a separator

OPTIONS:
    -s, --sep, --separator <sep>: The separator used to concatenate words [default: -]
    -c, --capitalize: Make each word all caps
    -h, --help: Show this message and exit

ARGS:
     <words>...: Any number of words to join (required)
$ deno run ./concat.ts
error: missing required value for <words...>
run with --help for more info
$ deno run ./concat.ts 'it'\''s' a me mario
it's-a-me-mario
$ deno run ./concat.ts -s _ snake case
snake_case
$ deno run ./concat.ts -cs_ screaming snake case
SCREAMING_SNAKE_CASE
$ deno run ./concat.ts --notaflag
error: unknown option `--notaflag`
if you meant to supply `--notaflag` as a value rather than a flag, use `-- --notaflag`
run with --help for more info
$ deno run ./concat.ts -s ' ' -- --notaflag is not a flag but now it works
--notaflag is not a flag but now it works