37 lines
861 B
Rust
37 lines
861 B
Rust
// run-pass
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#![allow(non_camel_case_types)]
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trait to_str {
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fn to_string_(&self) -> String;
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}
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impl to_str for isize {
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fn to_string_(&self) -> String { self.to_string() }
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}
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impl<T:to_str> to_str for Vec<T> {
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fn to_string_(&self) -> String {
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format!("[{}]",
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self.iter()
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.map(|e| e.to_string_())
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.collect::<Vec<String>>()
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.join(", "))
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}
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}
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pub fn main() {
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assert_eq!(1.to_string_(), "1".to_string());
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assert_eq!((vec![2, 3, 4]).to_string_(), "[2, 3, 4]".to_string());
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fn indirect<T:to_str>(x: T) -> String {
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format!("{}!", x.to_string_())
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}
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assert_eq!(indirect(vec![10, 20]), "[10, 20]!".to_string());
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fn indirect2<T:to_str>(x: T) -> String {
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indirect(x)
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}
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assert_eq!(indirect2(vec![1]), "[1]!".to_string());
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}
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