35 lines
871 B
Rust
35 lines
871 B
Rust
// errors4.rs
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//
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// Execute `rustlings hint errors4` or use the `hint` watch subcommand for a
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// hint.
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#[derive(PartialEq, Debug)]
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struct PositiveNonzeroInteger(u64);
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#[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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impl PositiveNonzeroInteger {
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fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
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// Hmm... Why is this always returning an Ok value?
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if value > 0 {
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Ok(PositiveNonzeroInteger(value as u64))
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} else {
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Err(if value == 0 { CreationError::Zero } else { CreationError::Negative })
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}
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}
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}
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#[test]
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fn test_creation() {
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assert!(PositiveNonzeroInteger::new(10).is_ok());
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assert_eq!(
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Err(CreationError::Negative),
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PositiveNonzeroInteger::new(-10)
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);
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assert_eq!(Err(CreationError::Zero), PositiveNonzeroInteger::new(0));
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}
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