rust / beginner
Snippet
Loop Labels and Early Exit
Rust allows you to label loops with a lifetime specifier like 'outer. This lets you break out of nested loops from the outer loop. The break without a label exits only the innermost loop, while break 'outer exits the labeled outer loop.
snippet.rs
rust
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let mut count = 0;'outer: loop {let mut inner = 0;loop {if inner == 2 {break;}inner += 1;}count += 1;if count == 3 {break 'outer;}}println!("Count: {}", count);
Breakdown
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'outer: loop {
Defines a labeled loop named 'outer'
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let mut inner = 0; loop {
Starts an inner unlabeled infinite loop
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if inner == 2 { break; }
Breaks inner loop when inner reaches 2
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if count == 3 { break 'outer; }
Breaks out of the labeled outer loop
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println!("Count: {}", count);
Final count is 3 after breaking outer loop