42 lines
935 B
Rust
42 lines
935 B
Rust
#[derive(PartialEq, Debug)]
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enum CreationError {
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Negative,
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Zero,
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}
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#[derive(PartialEq, Debug)]
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struct PositiveNonzeroInteger(u64);
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impl PositiveNonzeroInteger {
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fn new(value: i64) -> Result<Self, CreationError> {
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// TODO: This function shouldn't always return an `Ok`.
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match value {
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x if x < 0 => Err(CreationError::Negative),
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0 => Err(CreationError::Zero),
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_ => Ok(Self(value as u64))
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}
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}
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}
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fn main() {
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// You can optionally experiment here.
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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 test_creation() {
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assert_eq!(
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PositiveNonzeroInteger::new(10),
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Ok(PositiveNonzeroInteger(10)),
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);
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assert_eq!(
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PositiveNonzeroInteger::new(-10),
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Err(CreationError::Negative),
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);
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assert_eq!(PositiveNonzeroInteger::new(0), Err(CreationError::Zero));
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}
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}
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