diff options
Diffstat (limited to 'old_curriculum/error_handling/result1.rs')
| -rw-r--r-- | old_curriculum/error_handling/result1.rs | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/old_curriculum/error_handling/result1.rs b/old_curriculum/error_handling/result1.rs new file mode 100644 index 0000000..851ab45 --- /dev/null +++ b/old_curriculum/error_handling/result1.rs @@ -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 :) |
