43 lines
1.1 KiB
Plaintext
43 lines
1.1 KiB
Plaintext
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== Why is this an issue?
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When using a floating-point ``++while++`` loop counter, an accumulation of rounding errors may result in a mismatch between the expected and actual number of iterations.
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Even if floating-point loop counters appears to behave correctly on one implementation, it may give a different number of iterations on another implementation.
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== How to fix it
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To fix the issue, use an integer loop counter instead. This avoids the accumulation of rounding errors and ensures that the loop iterates the expected number of times.
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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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let mut counter = 0.0;
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while counter < 10.0 {
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println!("Counter: {}", counter);
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counter += 1.0;
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}
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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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let mut counter = 0;
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while counter < 10 {
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println!("Counter: {}", counter);
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counter += 1;
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}
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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#while_float
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