right let's try this one again

This commit is contained in:
olivia
2018-11-09 20:31:14 +01:00
parent 850a13e913
commit f7846af7ac
60 changed files with 130 additions and 939 deletions

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@@ -0,0 +1,43 @@
// result1.rs
// Make this test pass! Scroll down for hints :)
#[derive(PartialEq,Debug)]
struct PositiveNonzeroInteger(u64);
#[derive(PartialEq,Debug)]
enum CreationError {
Negative,
Zero,
}
impl PositiveNonzeroInteger {
fn new(value: i64) -> Result<PositiveNonzeroInteger, CreationError> {
Ok(PositiveNonzeroInteger(value as u64))
}
}
#[test]
fn test_creation() {
assert!(PositiveNonzeroInteger::new(10).is_ok());
assert_eq!(Err(CreationError::Negative), PositiveNonzeroInteger::new(-10));
assert_eq!(Err(CreationError::Zero), PositiveNonzeroInteger::new(0));
}
// `PositiveNonzeroInteger::new` is always creating a new instance and returning an `Ok` result.
// It should be doing some checking, returning an `Err` result if those checks fail, and only
// returning an `Ok` result if those checks determine that everything is... okay :)