134 lines
2.8 KiB
Rust
134 lines
2.8 KiB
Rust
#![feature(never_type)]
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#![allow(unreachable_code)]
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#[allow(unused)]
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fn never_returns() {
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loop {
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break loop {};
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}
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}
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pub fn main() {
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let value = 'outer: loop {
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if 1 == 1 {
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break 13;
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} else {
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let _never: ! = loop {
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break loop {
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break 'outer panic!();
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}
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};
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}
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};
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assert_eq!(value, 13);
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let x = [1, 3u32, 5];
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let y = [17];
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let z = [];
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let coerced: &[_] = loop {
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match 2 {
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1 => break &x,
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2 => break &y,
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3 => break &z,
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_ => (),
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}
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};
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assert_eq!(coerced, &[17u32]);
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let trait_unified = loop {
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break if true {
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break Default::default()
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} else {
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break [13, 14]
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};
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};
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assert_eq!(trait_unified, [0, 0]);
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let trait_unified_2 = loop {
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if false {
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break [String::from("Hello")]
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} else {
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break Default::default()
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};
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};
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// compare lengths; ptr comparison is not deterministic
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assert_eq!(trait_unified_2.len(), 1);
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assert_eq!(trait_unified_2[0].len(), 0);
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let trait_unified_3 = loop {
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break if false {
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break [String::from("Hello")]
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} else {
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["Yes".into()]
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};
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};
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assert_eq!(trait_unified_3, ["Yes"]);
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let regular_break = loop {
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if true {
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break;
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} else {
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break break Default::default();
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}
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};
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assert_eq!(regular_break, ());
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let regular_break_2 = loop {
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if true {
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break Default::default();
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} else {
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break;
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}
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};
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assert_eq!(regular_break_2, ());
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let regular_break_3 = loop {
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break if true {
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Default::default()
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} else {
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break;
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}
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};
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assert_eq!(regular_break_3, ());
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let regular_break_4 = loop {
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break ();
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break;
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};
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assert_eq!(regular_break_4, ());
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let regular_break_5 = loop {
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break;
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break ();
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};
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assert_eq!(regular_break_5, ());
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let nested_break_value = 'outer2: loop {
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let _a: u32 = 'inner: loop {
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if true {
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break 'outer2 "hello";
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} else {
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break 'inner 17;
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}
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};
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panic!();
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};
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assert_eq!(nested_break_value, "hello");
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let break_from_while_cond = loop {
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'inner_loop: while break 'inner_loop {
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panic!();
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}
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break 123;
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};
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assert_eq!(break_from_while_cond, 123);
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let break_from_while_to_outer = 'outer_loop: loop {
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while break 'outer_loop 567 {
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panic!("from_inner");
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}
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panic!("from outer");
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};
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assert_eq!(break_from_while_to_outer, 567);
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}
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