Trait frunk_core::labelled::LabelledGeneric [−] [src]

pub trait LabelledGeneric {
    type Repr;
    fn into(self) -> Self::Repr;
    fn from(r: Self::Repr) -> Self;

    fn convert_from<A>(a: A) -> Self
    where
        A: LabelledGeneric<Repr = Self::Repr>,
        Self: Sized,
    { ... }
    fn sculpted_convert_from<A, Indices>(a: A) -> Self
    where
        A: LabelledGeneric,
        Self: Sized,
        <A as LabelledGeneric>::Repr: Sculptor<Self::Repr, Indices>,
    { ... }
    fn transform_from<A, Indices>(a: A) -> Self
    where
        A: LabelledGeneric,
        Self: Sized,
        <A as LabelledGeneric>::Repr: Sculptor<Self::Repr, Indices>,
    { ... }
}

A trait that converts from a type to a labelled generic representation

LabelledGenerics allow us to have completely type-safe, boilerplate free conversions between different structs.

For the most part, you should be using the derivation that is available through frunk_derive to generate instances of this typeclass for your types.

Examples

use frunk_core::hlist::*;
use frunk_core::labelled::*;
#[derive(LabelledGeneric)]
struct NewUser<'a> {
    first_name: &'a str,
    last_name: &'a str,
    age: usize,
}

// Notice that the fields are mismatched in terms of ordering
#[derive(LabelledGeneric)]
struct SavedUser<'a> {
    last_name: &'a str,
    age: usize,
    first_name: &'a str,
}

let n_user = NewUser {
    first_name: "Joe",
    last_name: "Blow",
    age: 30,
};

// transform_from automagically sculpts the labelled generic
// representation of the source object to that of the target type
let s_user: SavedUser = transform_from(n_user); // doneRun

Associated Types

The labelled generic representation type

Required Methods

Go from something to Repr

Go from labelled Repr to something

Provided Methods

From one type to another using a type with a compatible labelled generic representation

Deprecated

Converts from another type A into Self assuming that A and Self have labelled generic representations that can be sculpted into each other.

Note that this method tosses away the "remainder" of the sculpted representation. In other words, anything that is not needed from A gets tossed out.

Converts from another type A into Self assuming that A and Self have labelled generic representations that can be sculpted into each other.

Note that this method tosses away the "remainder" of the sculpted representation. In other words, anything that is not needed from A gets tossed out.

Implementors