arg

Creators for positional args. See the Args guide for usage.

arg

const arg: {
	string<C extends string = string, N extends string | undefined = undefined>(options: ArgOptions<N> & StringOptions<C>): Arg<C | undefined, C, N>;
	number<N>(options: ArgOptions<N> & NumberOptions): Arg<number | undefined, number, N>;
	url<N>(options: ArgOptions<N>): Arg<URL | undefined, URL, N>;
	email<N>(options: ArgOptions<N>): Arg<string | undefined, string, N>;
	directory<N>(options: ArgOptions<N> & PathOptions): Arg<string | undefined, string, N>;
	file<N>(options: ArgOptions<N> & PathOptions): Arg<string | undefined, string, N>;
	custom<V, O>(parse: Parse<V, O>, valueName?: string): <N>(options: ArgOptions<N> & O) => Arg<V | undefined, V, N>;
	schema<S extends StandardSchemaV1>(schema: S, valueName?: string): <N>(options: ArgOptions<N>) => Arg<SchemaOutput<S> | undefined, SchemaOutput<S>, N>;
};

The creators match flag's value flags. There are no switches.

Arg

A positional arg. T is the resolved type, V is what one value parses to, and N is its name when given as a literal, which is used to check dynamic segments. Extends Param.

class Arg<T, V extends Defined, N extends string | undefined = undefined> extends Param<T, V> {
	readonly kind: 'arg';
	readonly options: ArgOptions<N>;
	required(required?: boolean): Arg<…>;
	multiple(allow?: boolean): Arg<…>;
	default(value: DefaultValue<T, V>): Arg<…>;
}

The modifiers work like Flag's. Args are optional by default, and at most one arg in a command can be .multiple().

ArgOptions

interface ArgOptions<N extends string | undefined = string | undefined> {
	description: string;
	name?: N;
}

Option	Description
description	Shown in help.
name	Display name in usage, e.g. 'files' → <files>. Defaults to the value type's name. Also binds the arg to a :name dynamic segment.

ArgList

type ArgList = readonly AnyArg[];

A tuple of args, as passed to args.

AnyArg

type AnyArg = Arg<any, any, any>;

Any arg, for constraints in generic code.