Trait OptionExt

pub trait OptionExt<T>: Sealed
where
    T: Assign<T, T>,
{
    // Required method
    fn option_assign(&mut self, src: T);
}

Extension trait to provide a method for setting a component on an Option<Self> if the Option is currently None. If the Option is Some, the method will delegate to the Assign trait’s assign method.

Type Parameters

• T: The type of the component to be set on the implementing object. This type represents the final form of the component as it should be stored or represented in the object.

Examples

Using option_assign to set a component on an Option:

use former_types::{ Assign, OptionExt }; // use crate `former` instead of crate `former_types` unless you need to use crate `former_types` directly

struct MyStruct
{
  name : String,
}

impl< IntoT : Into< MyStruct > > Assign< MyStruct, IntoT > for MyStruct
{
  fn assign( &mut self, component : IntoT )
  {
    self.name = component.into().name;
  }
}

let mut opt_struct: Option< MyStruct > = None;
opt_struct.option_assign( MyStruct { name: "New Name".to_string() } );
assert_eq!( opt_struct.unwrap().name, "New Name" );

Required Methods

fn option_assign(&mut self, src: T)

Sets the component on the Option if it is None.

If the Option is Some, the assign method is called to update the existing value.

Parameters

• src: The value to assign to the Option.

Implementations on Foreign Types

impl<T> OptionExt<T> for Option<T>

where T: Assign<T, T>,

fn option_assign(&mut self, src: T)

Implementors