45 lines
914 B
Rust
45 lines
914 B
Rust
// traits1.rs
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// Time to implement some traits!
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//
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// Your task is to implement the trait
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// `AppendBar` for the type `String`.
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//
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// The trait AppendBar has only one function,
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// which appends "Bar" to any object
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// implementing this trait.
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// Execute `rustlings hint traits1` or use the `hint` watch subcommand for a hint.
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trait AppendBar {
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fn append_bar(self) -> Self;
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}
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impl AppendBar for String {
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fn append_bar(self) -> String {
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format!("{}Bar", self)
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}
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}
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fn main() {
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let s = String::from("Foo");
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let s = s.append_bar();
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println!("s: {}", s);
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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 is_foo_bar() {
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assert_eq!(String::from("Foo").append_bar(), String::from("FooBar"));
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}
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#[test]
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fn is_bar_bar() {
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assert_eq!(
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String::from("").append_bar().append_bar(),
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String::from("BarBar")
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);
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}
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}
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