33 lines
940 B
Plaintext
33 lines
940 B
Plaintext
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== Why is this an issue?
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Empty ranges result in no iterations, making any loop a no-op. Trying to index slices using reversed ranges will result in runtime panics. Both scenarios lead to bugs or logical errors in the code.
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=== Code examples
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==== Noncompliant code example
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[source,rust,diff-id=1,diff-type=noncompliant]
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----
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fn main() {
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(10..=0).for_each(|x| println!("{}", x)); // Noncompliant: Empty range
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let arr = [1, 2, 3, 4, 5];
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let sub = &arr[3..1]; // Noncompliant: Reversed slice indexing
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}
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----
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==== Compliant solution
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[source,rust,diff-id=1,diff-type=compliant]
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----
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fn main() {
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(0..=10).rev().for_each(|x| println!("{}", x)); // Compliant: Properly reversed range for iteration
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let arr = [1, 2, 3, 4, 5];
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let sub = &arr[1..3]; // Compliant: Valid slice indexing
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}
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----
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== Resources
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=== Documentation
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* Clippy Lints - https://rust-lang.github.io/rust-clippy/master/index.html#reversed_empty_ranges
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