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// run-pass
#![allow(dead_code)]
trait Range {
const FIRST: u8;
const LAST: u8;
}
struct OneDigit;
impl Range for OneDigit {
const FIRST: u8 = 0;
const LAST: u8 = 9;
}
struct TwoDigits;
impl Range for TwoDigits {
const FIRST: u8 = 10;
const LAST: u8 = 99;
}
struct ThreeDigits;
impl Range for ThreeDigits {
const FIRST: u8 = 100;
const LAST: u8 = 255;
}
fn digits(x: u8) -> u32 {
match x {
OneDigit::FIRST..=OneDigit::LAST => 1,
TwoDigits::FIRST..=TwoDigits::LAST => 2,
ThreeDigits::FIRST..=ThreeDigits::LAST => 3,
}
}
fn main() {
assert_eq!(digits(100), 3);
}
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