Add Array::windows

[MINGtoMING]

Add Array::windows.

[peter-jerry-ye-code-review]

No input validation for window size parameter

Category
Correctness
Code Snippet
pub fn Array::windows[T](self : Array[T], size : Int) -> Array[ArrayView[T]] {
Recommendation
Add validation to ensure size > 0:

if size <= 0 {
  // handle error case or return empty array
}

Reasoning
The function documentation states that size must be positive, but there's no runtime check. Negative or zero sizes could cause unexpected behavior or panics.

Array capacity could be pre-calculated more efficiently

Category
Performance
Code Snippet
let windows = Array::new(capacity=len)
Recommendation
Calculate capacity inline:

let windows = Array::new(capacity=if self.length() < size { 0 } else { self.length() - size + 1 })```
**Reasoning**
Current implementation calculates length and does bounds checking twice - once for the length check and once for capacity. This could be combined into a single calculation.

</details>
<details>

<summary> Test cases could be more comprehensive </summary>

**Category**
Maintainability
**Code Snippet**
test "array_windows" {
  let arr = [1, 2, 3, 4, 5, 6]
  let windows = arr.windows(11)
**Recommendation**
Add test cases for edge cases:
- Empty array input
- Window size equal to array length
- Window size of 2 (common use case)
- Error cases if input validation is added
**Reasoning**
While current tests cover basic functionality, adding more edge cases would help ensure robustness and serve as documentation for expected behavior in these scenarios.

</details>

[coveralls]

Pull Request Test Coverage Report for Build 6627

Details

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.002%) to 92.364%

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Totals
Change from base Build 6625:	0.002%
Covered Lines:	6133
Relevant Lines:	6640

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💛 - Coveralls

[FlyCloudC]

How about return an Array[ArrayView[T]]?

[MINGtoMING]

I agree. Array::windows is typically used in read-only scenarios as well. However, the func interface differs from existing chunks/chunk_by impl, so perhaps they need to be adjusted together.