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use crate::{Color, Widget};
pub struct Element<'a, Message> {
pub(crate) widget: Box<dyn Widget<Message> + 'a>,
}
impl<'a, Message> Element<'a, Message> {
pub fn new(widget: impl Widget<Message> + 'a) -> Self {
Self {
widget: Box::new(widget),
}
}
pub fn explain(self, color: Color) -> Element<'a, Message> {
self
}
pub fn map<F, B>(self, f: F) -> Element<'a, B>
where
Message: 'static,
B: 'static,
F: 'static + Fn(Message) -> B,
{
Element {
widget: Box::new(Map::new(self.widget, f)),
}
}
}
struct Map<'a, A, B> {
widget: Box<dyn Widget<A> + 'a>,
mapper: Box<dyn Fn(A) -> B>,
}
impl<'a, A, B> Map<'a, A, B> {
pub fn new<F>(widget: Box<dyn Widget<A> + 'a>, mapper: F) -> Map<'a, A, B>
where
F: 'static + Fn(A) -> B,
{
Map {
widget,
mapper: Box::new(mapper),
}
}
}
impl<'a, A, B> Widget<B> for Map<'a, A, B> {}
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