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// issue: rust-lang/rust#99945
// ICE Failed to normalize
#![feature(type_alias_impl_trait)]
trait Widget<E> {
type State;
fn make_state(&self) -> Self::State;
}
impl<E> Widget<E> for () {
type State = ();
fn make_state(&self) -> Self::State {}
}
struct StatefulWidget<F>(F);
type StateWidget<'a> = impl Widget<&'a ()>;
impl<F: for<'a> Fn(&'a ()) -> StateWidget<'a>> Widget<()> for StatefulWidget<F> {
type State = ();
fn make_state(&self) -> Self::State {}
//~^ ERROR item does not constrain
}
fn new_stateful_widget<F: for<'a> Fn(&'a ()) -> StateWidget<'a>>(build: F) -> impl Widget<()> {
//~^ ERROR item does not constrain
StatefulWidget(build)
//~^ ERROR expected generic lifetime parameter, found `'a`
}
fn main() {
new_stateful_widget(|_| ()).make_state();
//~^ ERROR mismatched types
}
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