51369b610e
When an include is not surrounded by empty lines, its content is inlined on the same line as the adjacent content. That can lead to broken tags and other display issues. This PR fixes all such includes and introduces a validation step that forbids introducing the same problem again.
36 lines
1.9 KiB
Plaintext
36 lines
1.9 KiB
Plaintext
== Why is this an issue?
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Certain https://learn.microsoft.com/en-us/dotnet/visual-basic/programming-guide/language-features/operators-and-expressions/logical-and-bitwise-operators#bitwise-operations[bitwise operations] are not needed and should not be performed because their results are predictable.
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Specifically, using `And -1` with any value always results in the original value.
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That is because the binary representation of `-1` on a https://learn.microsoft.com/en-us/dotnet/visual-basic/programming-guide/language-features/data-types/numeric-data-types[numeric data type] supporting negative numbers, such as `Integer` or `Long`, is based on https://en.wikipedia.org/wiki/Two%27s_complement[two's complement] and made of all 1s: `&B111...111`.
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Performing `And` between a value and `&B111...111` means applying the `And` operator to each bit of the value and the bit `1`, resulting in a value equal to the provided one, bit by bit.
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[source,vbnet]
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----
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anyValue And -1 ' Noncompliant
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anyValue ' Compliant
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----
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Similarly, `anyValue Or 0` always results in `anyValue`, because the binary representation of `0` is always `&B000...000` and the `Or` operator returns its first input when the second is `0`.
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[source,vbnet]
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----
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anyValue Or 0 ' Noncompliant
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anyValue ' Compliant
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----
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The same applies to `anyValue Xor 0`: the `Xor` operator returns `1` when its two input bits are different (`1` and `0` or `0` and `1`) and returns `0` when its two input bits are the same (both `0` or both `1`).
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When `Xor` is applied with `0`, the result would be `1` if the other input is `1`, because the two input bits are different, and `0` if the other input bit is `0`, because the two input are the same. That results in returning `anyValue`.
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[source,vbnet]
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----
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anyValue Xor 0 ' Noncompliant
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anyValue ' Compliant
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----
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include::../resources-dotnet.adoc[]
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include::../rspecator.adoc[] |