mirror of https://github.com/rust-lang/rust
39 lines
637 B
Rust
39 lines
637 B
Rust
//@ run-pass
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#![allow(dead_code)]
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trait Range {
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const FIRST: u8;
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const LAST: u8;
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}
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struct OneDigit;
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impl Range for OneDigit {
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const FIRST: u8 = 0;
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const LAST: u8 = 9;
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}
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struct TwoDigits;
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impl Range for TwoDigits {
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const FIRST: u8 = 10;
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const LAST: u8 = 99;
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}
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struct ThreeDigits;
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impl Range for ThreeDigits {
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const FIRST: u8 = 100;
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const LAST: u8 = 255;
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}
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fn digits(x: u8) -> u32 {
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match x {
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OneDigit::FIRST..=OneDigit::LAST => 1,
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TwoDigits::FIRST..=TwoDigits::LAST => 2,
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ThreeDigits::FIRST..=ThreeDigits::LAST => 3,
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}
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}
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fn main() {
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assert_eq!(digits(100), 3);
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}
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