Class: MassargOption<OptionType, Args>

option.MassargOption

An option that can be passed to a command.

Options can be specified in two ways:

• Using the long form, e.g. --option value
• Using the short form, e.g. -o value

They can also have a parse function, which will be used to parse the value passed in from the original argument (string).

Example

massarg(options).option({
  name: 'option',
  description: 'An option',
  defaultValue: 'default',
  aliases: ['o'],
  parse: (value) => value.toUpperCase(),
})

Type parameters

Name	Type
OptionType	extends any = unknown
Args	extends ArgsObject = ArgsObject

Hierarchy

• MassargOption

  ↳ MassargNumber

  ↳ MassargFlag

Implements

• OptionConfig<OptionType, Args>

Constructors

constructor

• new MassargOption<OptionType, Args>(options): MassargOption<OptionType, Args>

Type parameters

Name	Type
OptionType	extends unknown = unknown
Args	extends ArgsObject = ArgsObject

Parameters

Name	Type	Description
options	Object	-
options.name	string	Name of the option
options.description	string	Description of the option, displayed in the help output
options.aliases	string[]	Aliases for the option, which can be used with the shorthand option notation.
options.defaultValue?	any	Default value of the option
options.array?	boolean	Whether the option is an array. Array options can be specified multiple times, and the values will be collected into an array. Normally, specifying an option multiple times will override the previous value.
options.required?	boolean	Whether the option is required. If it is required, parsing will throw an error if it's not present.
options.isDefault?	boolean	Whether the option is the default option. The default option is the option that is used if no other option is specified, e.g. a value is passed in without an option name. Note that if commands match the same argument first, they will be used instead of the default option.
options.hidden?	boolean	Whether the option is hidden. Hidden options are not displayed in the help output.
options.outputName?	string	Specify a custom name for the output, which will be used when parsing the args.
options.parse?	Parser<Args, OptionType>	Parse the value of the option. You can return any type here, or throw an error if the value is invalid.

Returns

MassargOption<OptionType, Args>

Defined in

src/option.ts:192

Properties

name

• name: string

Implementation of

OptionConfig.name

Defined in

src/option.ts:177

---

description

• description: string

Implementation of

OptionConfig.description

Defined in

src/option.ts:178

---

defaultValue

• Optional defaultValue: OptionType

Implementation of

OptionConfig.defaultValue

Defined in

src/option.ts:179

---

aliases

• aliases: string[]

Implementation of

OptionConfig.aliases

Defined in

src/option.ts:180

---

parse

• parse: Parser<Args, OptionType>

Implementation of

OptionConfig.parse

Defined in

src/option.ts:181

---

isArray

• isArray: boolean

Whether this option can be used multiple times. Any passed values will end up in an array instead of each usage overwriting the existing value.

Defined in

src/option.ts:186

---

isRequired

• isRequired: boolean

Whether this option is required. Failing to specify this option will throw an error.

Defined in

src/option.ts:188

---

isDefault

• isDefault: boolean

Implementation of

OptionConfig.isDefault

Defined in

src/option.ts:189

---

outputName

• Optional outputName: string

Implementation of

OptionConfig.outputName

Defined in

src/option.ts:190

Methods

fromTypedConfig

▸ fromTypedConfig<T, A>(config): MassargOption<T, ArgsObject>

Create a typed option from a configuration. Currently supports number options which are automatically transformed from string to number.

Type parameters

Name	Type
T	unknown
A	extends ArgsObject = ArgsObject

Parameters

Name	Type
config	Object
config.name	string
config.description	string
config.aliases	string[]
config.type	undefined | "number"
config.defaultValue	any
config.array	undefined | boolean
config.required	undefined | boolean
config.isDefault	undefined | boolean
config.hidden	undefined | boolean
config.outputName	undefined | string
config.parse	undefined | Parser<A, T>

Returns

MassargOption<T, ArgsObject>

Defined in

src/option.ts:209

---

getOutputName

▸ getOutputName(): string

Returns the key which this option outputs to in the final object.

Returns

string

Default

The camelCase version of this option's name.

Can be overridden with {@link outputName}.

Defined in

src/option.ts:226

---

helpString

▸ helpString(): string

Get the help string for this option

Returns

string

Defined in

src/option.ts:260

---

isMatch

▸ isMatch(arg, prefixes): boolean

Returns true if the flag (including any prefixes) matches the name or aliases

Parameters

Name	Type
arg	string
prefixes	Prefixes

Returns

boolean

Defined in

src/option.ts:266

---

qualifiedNames

▸ qualifiedNames(prefixes): QualifiedNames

Return the finalized names that will cause this option to match.

Parameters

Name	Type
prefixes	Prefixes

Returns

QualifiedNames

Defined in

src/option.ts:277