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// run-pass
#![allow(dead_code)]
#![allow(unused_assignments)]
#![feature(label_break_value)]
// Test control flow to follow label_break_value semantics
fn label_break(a: bool, b: bool) -> u32 {
let mut v = 0;
'b: {
v = 1;
if a {
break 'b;
}
v = 2;
if b {
break 'b;
}
v = 3;
}
return v;
}
// Test that values can be returned
fn break_value(a: bool, b: bool) -> u32 {
let result = 'block: {
if a { break 'block 1; }
if b { break 'block 2; }
3
};
result
}
// Test nesting of labeled blocks
// here we only check that it compiles
fn label_break_nested() {
'b: {
println!("hi");
if false {
break 'b;
}
'c: {
if false {
break 'b;
}
break 'c;
}
println!("hello");
if true {
break 'b;
}
}
}
// Tests for mixing labeled blocks with loop constructs
// This function should be the identity function
fn label_break_mixed(v: u32) -> u32 {
let mut r = 0;
'b: {
// Unlabeled break still works
// (only crossing boundaries is an error)
loop {
break;
}
if v == 0 {
break 'b;
}
// Labeled breaking an inner loop still works
'c: loop {
if r == 1 {
break 'c;
}
r += 1;
}
assert_eq!(r, 1);
if v == 1 {
break 'b;
}
// Labeled breaking an outer loop still works
'd: loop {
{
if v == r {
break 'b;
}
if r == 5 {
break 'd;
}
r += 1;
}
}
assert_eq!(r, 5);
assert!(v > r);
// Here we test return from inside a labeled block
return v;
}
r
}
pub fn main() {
assert_eq!(label_break(true, false), 1);
assert_eq!(label_break(false, true), 2);
assert_eq!(label_break(false, false), 3);
assert_eq!(break_value(true, false), 1);
assert_eq!(break_value(false, true), 2);
assert_eq!(break_value(false, false), 3);
assert_eq!(label_break_mixed(0), 0);
assert_eq!(label_break_mixed(1), 1);
assert_eq!(label_break_mixed(2), 2);
assert_eq!(label_break_mixed(3), 3);
assert_eq!(label_break_mixed(4), 4);
assert_eq!(label_break_mixed(5), 5);
assert_eq!(label_break_mixed(6), 6);
// FIXME: ensure that labeled blocks work if produced by macros and in match arms
}
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