Enum Optionality

pub enum Optionality {
    Required,
    Optional,
    Repeating,
    Greedy,
}

The optionality defines the requirments related to the presence of the argument on the command line.

Variants

Required

Required indicates the argument is required exactly once.

Optional

Optional indicates the argument may or may not be present.

Repeating

Repeating indicates the argument may appear zero or more times.

Greedy

Greedy is used for positional arguments which capture the all command line input upto the next flag or the end of the input.

Trait Implementations

impl Debug for Optionality

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Default for Optionality

fn default() -> Optionality

Returns the “default value” for a type.

impl PartialEq for Optionality

fn eq(&self, other: &Optionality) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for Optionality

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for Optionality

impl StructuralPartialEq for Optionality