Struct OptionBrand 

pub struct OptionBrand;

Brand for Option.

Trait Implementations

impl ApplyFirst for OptionBrand

fn apply_first<'a, A: 'a + Clone, B: 'a + Clone>( fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, fb: <Self as Kind_c3c3610c70409ee6>::Of<'a, B>, ) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, A>

Combines two contexts, keeping the value from the first context.

impl ApplySecond for OptionBrand

fn apply_second<'a, A: 'a + Clone, B: 'a + Clone>( fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, fb: <Self as Kind_c3c3610c70409ee6>::Of<'a, B>, ) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, B>

Combines two contexts, keeping the value from the second context.

impl Clone for OptionBrand

fn clone(&self) -> OptionBrand

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for OptionBrand

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

Formats the value using the given formatter.

impl Default for OptionBrand

fn default() -> OptionBrand

Returns the “default value” for a type.

impl Foldable for OptionBrand

fn fold_right<'a, FnBrand, Func, A: 'a, B: 'a>( func: Func, initial: B, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> B

where Func: Fn(A, B) -> B + 'a, FnBrand: ClonableFn + 'a,

Folds the option from the right.

This method performs a right-associative fold of the option. If the option is Some(a), it applies the function to a and the initial value. If None, it returns the initial value.

Type Signature

forall a b. Foldable Option => ((a, b) -> b, b, Option a) -> b

Parameters

• func: The folding function.
• initial: The initial value.
• fa: The option to fold.

Returns

func(a, initial) if fa is Some(a), otherwise initial.

Examples

use fp_library::classes::foldable::Foldable;
use fp_library::brands::OptionBrand;
use fp_library::brands::RcFnBrand;

let x = Some(5);
let y = OptionBrand::fold_right::<RcFnBrand, _, _, _>(|a, b| a + b, 10, x);
assert_eq!(y, 15);

// Using the free function
use fp_library::classes::foldable::fold_right;
assert_eq!(fold_right::<RcFnBrand, OptionBrand, _, _, _>(|x: i32, acc| x + acc, 0, Some(5)), 5);
assert_eq!(fold_right::<RcFnBrand, OptionBrand, _, _, _>(|x: i32, acc| x + acc, 0, None), 0);

fn fold_left<'a, FnBrand, Func, A: 'a, B: 'a>( func: Func, initial: B, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> B

where Func: Fn(B, A) -> B + 'a, FnBrand: ClonableFn + 'a,

Folds the option from the left.

This method performs a left-associative fold of the option. If the option is Some(a), it applies the function to the initial value and a. If None, it returns the initial value.

Type Signature

forall a b. Foldable Option => ((b, a) -> b, b, Option a) -> b

Parameters

• func: The function to apply to the accumulator and each element.
• initial: The initial value of the accumulator.
• fa: The option to fold.

Returns

f(initial, a) if fa is Some(a), otherwise initial.

Examples

use fp_library::classes::foldable::Foldable;
use fp_library::brands::OptionBrand;
use fp_library::brands::RcFnBrand;

let x = Some(5);
let y = OptionBrand::fold_left::<RcFnBrand, _, _, _>(|b, a| b + a, 10, x);
assert_eq!(y, 15);

// Using the free function
use fp_library::classes::foldable::fold_left;
assert_eq!(fold_left::<RcFnBrand, OptionBrand, _, _, _>(|acc, x: i32| acc + x, 0, Some(5)), 5);

fn fold_map<'a, FnBrand, Func, A: 'a, M>( func: Func, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> M

where M: Monoid + 'a, Func: Fn(A) -> M + 'a, FnBrand: ClonableFn + 'a,

Maps the value to a monoid and returns it, or returns empty.

This method maps the element of the option to a monoid. If the option is None, it returns the monoid’s identity element.

Type Signature

forall a m. (Foldable Option, Monoid m) => ((a) -> m, Option a) -> m

Parameters

• func: The mapping function.
• fa: The option to fold.

Returns

func(a) if fa is Some(a), otherwise M::empty().

Examples

use fp_library::classes::foldable::Foldable;
use fp_library::brands::OptionBrand;
use fp_library::types::string; // Import to bring Monoid impl for String into scope
use fp_library::brands::RcFnBrand;

let x = Some(5);
let y = OptionBrand::fold_map::<RcFnBrand, _, _, _>(|a: i32| a.to_string(), x);
assert_eq!(y, "5".to_string());

// Using the free function
use fp_library::classes::foldable::fold_map;
assert_eq!(fold_map::<RcFnBrand, OptionBrand, _, _, _>(|x: i32| x.to_string(), Some(5)), "5".to_string());

impl Functor for OptionBrand

fn map<'a, F, A: 'a, B: 'a>( f: F, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, B>

where F: Fn(A) -> B + 'a,

Maps a function over the value in the option.

This method applies a function to the value inside the option, producing a new option with the transformed value. If the option is None, it returns None.

Type Signature

forall a b. Functor Option => (a -> b, Option a) -> Option b

Parameters

• f: The function to apply to the value.
• fa: The option to map over.

Returns

A new option containing the result of applying the function, or None.

Examples

use fp_library::classes::functor::Functor;
use fp_library::brands::OptionBrand;

let x = Some(5);
let y = OptionBrand::map(|i| i * 2, x);
assert_eq!(y, Some(10));

// Using the free function
use fp_library::classes::functor::map;
assert_eq!(map::<OptionBrand, _, _, _>(|x: i32| x * 2, Some(5)), Some(10));
assert_eq!(map::<OptionBrand, _, _, _>(|x: i32| x * 2, None), None);

impl Hash for OptionBrand

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Kind_c3c3610c70409ee6 for OptionBrand

Generated implementation of Kind_c3c3610c70409ee6 for OptionBrand.

type Of<'a, A: 'a> = Option<A>

impl Lift for OptionBrand

fn lift2<'a, F, A, B, C>( f: F, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, fb: <Self as Kind_c3c3610c70409ee6>::Of<'a, B>, ) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, C>

where F: Fn(A, B) -> C + 'a, A: 'a, B: 'a, C: 'a,

Lifts a binary function into the option context.

This method lifts a binary function to operate on values within the option context.

Type Signature

forall a b c. Lift Option => ((a, b) -> c, Option a, Option b) -> Option c

Parameters

• f: The binary function to apply.
• fa: The first option.
• fb: The second option.

Returns

Some(f(a, b)) if both options are Some, otherwise None.

Examples

use fp_library::classes::lift::Lift;
use fp_library::brands::OptionBrand;

let x = Some(1);
let y = Some(2);
let z = OptionBrand::lift2(|a, b| a + b, x, y);
assert_eq!(z, Some(3));

// Using the free function
use fp_library::classes::lift::lift2;
assert_eq!(lift2::<OptionBrand, _, _, _, _>(|x: i32, y: i32| x + y, Some(1), Some(2)), Some(3));
assert_eq!(lift2::<OptionBrand, _, _, _, _>(|x: i32, y: i32| x + y, Some(1), None), None);

impl Ord for OptionBrand

fn cmp(&self, other: &OptionBrand) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl<FnBrand: SendClonableFn> ParFoldable<FnBrand> for OptionBrand

fn par_fold_map<'a, A, M>( func: <FnBrand as SendClonableFn>::SendOf<'a, A, M>, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> M

where A: 'a + Clone + Send + Sync, M: Monoid + Send + Sync + 'a,

Maps the value to a monoid and returns it, or returns empty, in parallel.

This method maps the element of the option to a monoid. Since Option contains at most one element, no actual parallelism occurs, but the interface is satisfied.

Type Signature

forall a m. (ParFoldable Option, Monoid m, Send m, Sync m) => (f a m, Option a) -> m

Parameters

• func: The mapping function.
• fa: The option to fold.

Returns

The combined monoid value.

Examples

use fp_library::classes::par_foldable::ParFoldable;
use fp_library::brands::{OptionBrand, ArcFnBrand};
use fp_library::classes::send_clonable_fn::SendClonableFn;
use fp_library::classes::send_clonable_fn::new_send;

let x = Some(1);
let f = new_send::<ArcFnBrand, _, _>(|x: i32| x.to_string());
let y = <OptionBrand as ParFoldable<ArcFnBrand>>::par_fold_map(f, x);
assert_eq!(y, "1".to_string());

// Using the free function
use fp_library::classes::par_foldable::par_fold_map;
let x = Some(1);
let f = new_send::<ArcFnBrand, _, _>(|x: i32| x.to_string());
assert_eq!(par_fold_map::<ArcFnBrand, OptionBrand, _, _>(f, x), "1".to_string());

fn par_fold_right<'a, A, B>( func: <FnBrand as SendClonableFn>::SendOf<'a, (A, B), B>, init: B, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> B

where A: 'a + Clone + Send + Sync, B: Send + Sync + 'a, FnBrand: 'a,

Parallel version of fold_right.

impl PartialEq for OptionBrand

fn eq(&self, other: &OptionBrand) -> 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 PartialOrd for OptionBrand

fn partial_cmp(&self, other: &OptionBrand) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Pointed for OptionBrand

fn pure<'a, A: 'a>(a: A) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, A>

Wraps a value in an option.

This method wraps a value in an option context.

Type Signature

forall a. Pointed Option => a -> Option a

Parameters

• a: The value to wrap.

Returns

Some(a).

Examples

use fp_library::classes::pointed::Pointed;
use fp_library::brands::OptionBrand;

let x = OptionBrand::pure(5);
assert_eq!(x, Some(5));

// Using the free function
use fp_library::classes::pointed::pure;
assert_eq!(pure::<OptionBrand, _>(5), Some(5));

impl Semiapplicative for OptionBrand

fn apply<'a, FnBrand: 'a + ClonableFn, A: 'a + Clone, B: 'a>( ff: <Self as Kind_c3c3610c70409ee6>::Of<'a, <FnBrand as ClonableFn>::Of<'a, A, B>>, fa: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, B>

Applies a wrapped function to a wrapped value.

This method applies a function wrapped in an option to a value wrapped in an option.

Type Signature

forall a b. Semiapplicative Option => (Option (a -> b), Option a) -> Option b

Parameters

• ff: The option containing the function.
• fa: The option containing the value.

Returns

Some(f(a)) if both are Some, otherwise None.

Examples

use fp_library::classes::semiapplicative::Semiapplicative;
use fp_library::classes::clonable_fn::ClonableFn;
use fp_library::brands::{OptionBrand};
use fp_library::brands::RcFnBrand;
use std::rc::Rc;

let f = Some(<RcFnBrand as ClonableFn>::new(|x: i32| x * 2));
let x = Some(5);
let y = OptionBrand::apply::<RcFnBrand, i32, i32>(f, x);
assert_eq!(y, Some(10));

// Using the free function
use fp_library::classes::semiapplicative::apply;
let f = Some(<RcFnBrand as ClonableFn>::new(|x: i32| x * 2));
assert_eq!(apply::<RcFnBrand, OptionBrand, _, _>(f, Some(5)), Some(10));

impl Semimonad for OptionBrand

fn bind<'a, F, A: 'a, B: 'a>( ma: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, f: F, ) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, B>

where F: Fn(A) -> <Self as Kind_c3c3610c70409ee6>::Of<'a, B> + 'a,

Chains option computations.

This method chains two option computations, where the second computation depends on the result of the first.

Type Signature

forall a b. Semimonad Option => (Option a, a -> Option b) -> Option b

Parameters

• ma: The first option.
• f: The function to apply to the value inside the option.

Returns

The result of applying f to the value if ma is Some, otherwise None.

Examples

use fp_library::classes::semimonad::Semimonad;
use fp_library::brands::OptionBrand;

let x = Some(5);
let y = OptionBrand::bind(x, |i| Some(i * 2));
assert_eq!(y, Some(10));

// Using the free function
use fp_library::classes::semimonad::bind;
assert_eq!(bind::<OptionBrand, _, _, _>(Some(5), |x| Some(x * 2)), Some(10));
assert_eq!(bind::<OptionBrand, _, _, _>(None, |x: i32| Some(x * 2)), None);

impl Traversable for OptionBrand

fn traverse<'a, F: Applicative, Func, A: 'a + Clone, B: 'a + Clone>( func: Func, ta: <Self as Kind_c3c3610c70409ee6>::Of<'a, A>, ) -> <F as Kind_c3c3610c70409ee6>::Of<'a, <Self as Kind_c3c3610c70409ee6>::Of<'a, B>>

where Func: Fn(A) -> <F as Kind_c3c3610c70409ee6>::Of<'a, B> + 'a, <Self as Kind_c3c3610c70409ee6>::Of<'a, B>: Clone,

Traverses the option with an applicative function.

This method maps the element of the option to a computation, evaluates it, and wraps the result in the applicative context. If None, it returns pure(None).

Type Signature

forall a b f. (Traversable Option, Applicative f) => (a -> f b, Option a) -> f (Option b)

Parameters

• func: The function to apply to each element, returning a value in an applicative context.
• ta: The option to traverse.

Returns

The option wrapped in the applicative context.

Examples

use fp_library::classes::traversable::Traversable;
use fp_library::brands::OptionBrand;

let x = Some(5);
let y = OptionBrand::traverse::<OptionBrand, _, _, _>(|a| Some(a * 2), x);
assert_eq!(y, Some(Some(10)));

// Using the free function
use fp_library::classes::traversable::traverse;
assert_eq!(traverse::<OptionBrand, OptionBrand, _, _, _>(|x| Some(x * 2), Some(5)), Some(Some(10)));

fn sequence<'a, F: Applicative, A: 'a + Clone>( ta: <Self as Kind_c3c3610c70409ee6>::Of<'a, <F as Kind_c3c3610c70409ee6>::Of<'a, A>>, ) -> <F as Kind_c3c3610c70409ee6>::Of<'a, <Self as Kind_c3c3610c70409ee6>::Of<'a, A>>

where <F as Kind_c3c3610c70409ee6>::Of<'a, A>: Clone, <Self as Kind_c3c3610c70409ee6>::Of<'a, A>: Clone,

Sequences an option of applicative.

This method evaluates the computation inside the option and wraps the result in the applicative context. If None, it returns pure(None).

Type Signature

forall a f. (Traversable Option, Applicative f) => (Option (f a)) -> f (Option a)

Parameters

• ta: The option containing the applicative value.

Returns

The option wrapped in the applicative context.

Examples

use fp_library::classes::traversable::Traversable;
use fp_library::brands::OptionBrand;

let x = Some(Some(5));
let y = OptionBrand::sequence::<OptionBrand, _>(x);
assert_eq!(y, Some(Some(5)));

// Using the free function
use fp_library::classes::traversable::sequence;
assert_eq!(sequence::<OptionBrand, OptionBrand, _>(Some(Some(5))), Some(Some(5)));

impl Copy for OptionBrand

impl Eq for OptionBrand

impl StructuralPartialEq for OptionBrand