Derive Macro druid_derive::Lens

#[derive(Lens)]
{
    // Attributes available to this derive:
    #[lens]
}

Generates lenses to access the fields of a struct.

An associated constant is defined on the struct for each field, having the same name as the field.

This macro supports a lens field attribute with the following arguments:

• #[lens(ignore)] skips creating a lens for one field.
• #[lens(name="foo")] gives the lens the specified name (instead of the default, which is to create a lens with the same name as the field).

Example

use druid_derive::Lens;

#[derive(Lens)]
struct State {
    // The Lens derive will create a `State::text` constant implementing
    // `druid::Lens<State, String>`
    text: String,
    // The Lens derive will create a `State::lens_number` constant implementing
    // `druid::Lens<State, f64>`
    #[lens(name = "lens_number")]
    number: f64,
    // The Lens derive won't create anything for this field.
    #[lens(ignore)]
    blah: f64,
}