Struct Getter 

pub struct Getter<'a, PointerBrand, S, T, A, B>
where
    PointerBrand: UnsizedCoercible,
    S: 'a,
    T: 'a,
    A: 'a,
    B: 'a,
{
    pub view_fn: <FnBrand<PointerBrand> as Kind_266801a817966495>::Of<'a, S, A>,
    /* private fields */
}

A polymorphic getter.

Matches PureScript’s Getter s t a b.

Type Parameters

• 'a: The lifetime of the values.
• PointerBrand: The reference-counted pointer type.
• S: The source type of the structure.
• T: The target type of the structure.
• A: The source type of the focus.
• B: The target type of the focus.

Fields

view_fn: <FnBrand<PointerBrand> as Kind_266801a817966495>::Of<'a, S, A>

Function to view the focus of the getter in a structure.

Implementations

impl<'a, PointerBrand, S, T, A, B> Getter<'a, PointerBrand, S, T, A, B>

where PointerBrand: UnsizedCoercible, S: 'a, T: 'a, A: 'a, B: 'a,

Type Parameters

• 'a: The lifetime of the values.
• PointerBrand: The reference-counted pointer type.
• S: The source type of the structure.
• T: The target type of the structure.
• A: The source type of the focus.
• B: The target type of the focus.

pub fn new(view: impl 'a + Fn(S) -> A) -> Self

Create a new getter from a view function.

Type Signature

forall PointerBrand S T A B. UnsizedCoercible PointerBrand => (S -> A) -> Getter PointerBrand S T A B

Parameters

• view: The view function.

Returns

A new instance of the type.

Examples

use fp_library::{
	brands::RcBrand,
	types::optics::Getter,
};

let g: Getter<RcBrand, (i32, String), (i32, String), i32, i32> = Getter::new(|(x, _)| x);
assert_eq!(g.view((42, "hi".to_string())), 42);

pub fn view(&self, s: S) -> A

View the focus of the getter in a structure.

Type Signature

forall PointerBrand S T A B. UnsizedCoercible PointerBrand => (&Getter PointerBrand S T A B, S) -> A

Parameters

• &self: The getter instance.
• s: The structure to view.

Returns

The focus value.

Examples

use fp_library::{
	brands::RcBrand,
	types::optics::Getter,
};

let g: Getter<RcBrand, (i32, String), (i32, String), i32, i32> = Getter::new(|(x, _)| x);
assert_eq!(g.view((42, "hi".to_string())), 42);

Trait Implementations

impl<'a, PointerBrand, S, T, A, B> Clone for Getter<'a, PointerBrand, S, T, A, B>

where PointerBrand: UnsizedCoercible, S: 'a, T: 'a, A: 'a, B: 'a,

Type Parameters

• 'a: The lifetime of the values.
• PointerBrand: The reference-counted pointer type.
• S: The source type of the structure.
• T: The target type of the structure.
• A: The source type of the focus.
• B: The target type of the focus.

fn clone(&self) -> Self

Type Signature

forall PointerBrand S T A B. UnsizedCoercible PointerBrand => &Getter PointerBrand S T A B -> Getter PointerBrand S T A B

Returns

A new Getter instance that is a copy of the original.

Examples

use fp_library::{
	brands::RcBrand,
	types::optics::Getter,
};

let g: Getter<RcBrand, (i32, String), (i32, String), i32, i32> = Getter::new(|(x, _)| x);
let cloned = g.clone();
assert_eq!(cloned.view((42, "hi".to_string())), 42);

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

Performs copy-assignment from source.

impl<'a, PointerBrand, S, T, A, B, R, Q> Optic<'a, ForgetBrand<Q, R>, S, T, A, B> for Getter<'a, PointerBrand, S, T, A, B>

where PointerBrand: UnsizedCoercible, Q: UnsizedCoercible + 'static, S: 'a, T: 'a, A: 'a, B: 'a, R: 'a + 'static,

Type Parameters

• 'a: The lifetime of the values.
• PointerBrand: The reference-counted pointer type for the getter.
• S: The source type of the structure.
• T: The target type of the structure.
• A: The source type of the focus.
• B: The target type of the focus.
• R: The return type of the forget profunctor.
• Q: The reference-counted pointer type for the forget brand.

fn evaluate( &self, pab: <ForgetBrand<Q, R> as Kind_266801a817966495>::Of<'a, A, B>, ) -> <ForgetBrand<Q, R> as Kind_266801a817966495>::Of<'a, S, T>

Type Signature

forall PointerBrand S T A B R Q. (UnsizedCoercible PointerBrand, UnsizedCoercible Q) => (&Getter PointerBrand S T A B R Q, Forget Q R A B) -> Forget Q R S T

Parameters

• &self: The getter instance.
• pab: The profunctor value to transform.

Returns

The transformed profunctor value.

Examples

use fp_library::{
	brands::{
		optics::*,
		*,
	},
	classes::optics::*,
	functions::*,
	types::optics::*,
};

let g: Getter<RcBrand, (i32, String), (i32, String), i32, i32> = Getter::new(|(x, _)| x);
let f = Forget::<RcBrand, i32, i32, i32>::new(|x| x);
let folded = Optic::<ForgetBrand<RcBrand, i32>, _, _, _, _>::evaluate(&g, f);
assert_eq!(folded.run((42, "hi".to_string())), 42);