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* hashmaps * quiz, options * error01 * errors, generics * traits, quiz3 * lifetime, tests * iterators, smart pointers
26 lines
724 B
Rust
26 lines
724 B
Rust
// lifetimes1.rs
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//
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// 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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//
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// Execute `rustlings hint lifetimes1` or use the `hint` watch subcommand for a
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// hint.
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fn longest<'a>(x: &'a str, y: &'a str) -> &'a 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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let string1 = String::from("abcd");
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let string2 = "xyz";
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let result = longest(string1.as_str(), string2);
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println!("The longest string is '{}'", result);
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}
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