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29 lines
732 B
Rust
29 lines
732 B
Rust
// The Rust compiler needs to know how to check whether supplied references are
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// valid, so that it can let the programmer know if a reference is at risk of
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// going out of scope before it is used. Remember, references are borrows and do
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// not own their own data. What if their owner goes out of scope?
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// TODO: Fix the compiler error by updating the function signature.
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fn longest(x: &str, y: &str) -> &str {
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if x.len() > y.len() {
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x
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} else {
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y
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}
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}
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fn main() {
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// You can optionally experiment here.
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}
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#[cfg(test)]
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mod tests {
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use super::*;
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#[test]
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fn test_longest() {
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assert_eq!(longest("abcd", "123"), "abcd");
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assert_eq!(longest("abc", "1234"), "1234");
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}
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}
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