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//@ run-pass
// adapted from tests/ui/binding/if-let.rs
#![allow(dead_code)]
fn none() -> bool {
let None = Some("test") else {
return true;
};
false
}
fn ok() -> bool {
let Ok(()) = Err::<(),&'static str>("test") else {
return true;
};
false
}
pub fn main() {
let x = Some(3);
let Some(y) = x else {
panic!("let-else panicked");
};
assert_eq!(y, 3);
let Some(_) = x else {
panic!("bad match");
};
assert!(none());
assert!(ok());
assert!((|| {
let 1 = 2 else {
return true;
};
false
})());
enum Foo {
One,
Two(usize),
Three(String, isize),
}
let foo = Foo::Three("three".to_string(), 42);
let one = || {
let Foo::One = foo else {
return true;
};
false
};
assert!(one());
let two = || {
let Foo::Two(_x) = foo else {
return true;
};
false
};
assert!(two());
let three = || {
let Foo::Three(s, _x) = foo else {
return false;
};
s == "three"
};
assert!(three());
let a@Foo::Two(_) = Foo::Two(42_usize) else {
panic!("bad match")
};
let Foo::Two(b) = a else {
panic!("panic in nested `if let`");
};
assert_eq!(b, 42_usize);
}
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