Enum Outcome 

pub enum Outcome<T> {
    Parsed(T),
    Help(Printed),
    Version(Printed),
    Failed(Printed),
}

What one command line does to a CLI.

The four things parse() can do, as a value instead of a side effect: a struct, a page, a version, or a failure. A test asserting that ex with no arguments prints help is asserting on Outcome::Help, which is not something a Result can say.

Variants

Parsed(T)

It parsed.

Help(Printed)

Help was asked for — or shown because nothing was asked for at all, which is the case with stderr set and a non-zero code.

Version(Printed)

A version was asked for.

Failed(Printed)

The command line did not parse, and this is what the user reads.

Implementations

impl<T> Outcome<T>

pub fn parsed(self) -> T

The parsed struct, panicking with what the CLI would have printed instead.

pub fn printed(&self) -> Option<&Printed>

What would have been printed, for anything that is not a parse.

pub fn text(&self) -> Option<&str>

The text of Outcome::printed, for an assertion that only cares what it says.

Trait Implementations

impl<T: Clone> Clone for Outcome<T>

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T: Debug> Debug for Outcome<T>

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

Formats the value using the given formatter.

impl<T: Eq> Eq for Outcome<T>

impl<T: PartialEq> PartialEq for Outcome<T>

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

Equality operator ==.

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

Inequality operator !=.

impl<T: PartialEq> StructuralPartialEq for Outcome<T>