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