Trait OptionalArg 

pub trait OptionalArg: Sized {
    // Required methods
    fn parse(arg: impl AsRef<str>, arg: ArgRef) -> Result<Self, Error>;
    fn default() -> Self;

    // Provided method
    fn map_parse(
        val: Option<impl AsRef<str>>,
        arg: ArgRef,
    ) -> Result<Self, Error> { ... }
}

Required Methods

fn parse(arg: impl AsRef<str>, arg: ArgRef) -> Result<Self, Error>

fn default() -> Self

Provided Methods

fn map_parse(val: Option<impl AsRef<str>>, arg: ArgRef) -> Result<Self, Error>

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl<T: Argument> OptionalArg for Option<T>

fn parse(val: impl AsRef<str>, arg: ArgRef) -> Result<Self, Error>

fn default() -> Self

Implementors