Struct Maybe 

pub struct Maybe<A>(pub Option<A>);

A simple Maybe monad (equivalent to Option).

Tuple Fields

0: Option<A>

Implementations

impl<A> Maybe<A>

pub fn just(a: A) -> Self

Wrap a value as Just a.

pub fn nothing() -> Self

The Nothing constructor.

pub fn is_nothing(&self) -> bool

Return true if this is Nothing.

pub fn is_just(&self) -> bool

Return true if this is Just _.

pub fn bind<B>(self, f: impl FnOnce(A) -> Maybe<B>) -> Maybe<B>

Monadic bind.

pub fn fmap<B>(self, f: impl FnOnce(A) -> B) -> Maybe<B>

Functor map.

pub fn into_option(self) -> Option<A>

Return the inner Option.

pub fn or_else(self, other: Maybe<A>) -> Maybe<A>

Alternative: use other if self is Nothing.

Trait Implementations

impl<A: Clone> Clone for Maybe<A>

fn clone(&self) -> Maybe<A>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<A: Debug> Debug for Maybe<A>

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

Formats the value using the given formatter.

impl<A: PartialEq> PartialEq for Maybe<A>

fn eq(&self, other: &Maybe<A>) -> 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<A: Eq> Eq for Maybe<A>

impl<A> StructuralPartialEq for Maybe<A>