src/tools/clippy/src/docs/ineffective_bit_mask.txt

   1 ### What it does
   2 Checks for bit masks in comparisons which can be removed
   3 without changing the outcome. The basic structure can be seen in the
   4 following table:
   5
   6 |Comparison| Bit Op   |Example     |equals |
   7 |----------|----------|------------|-------|
   8 |`>` / `<=`|`\|` / `^`|`x \| 2 > 3`|`x > 3`|
   9 |`<` / `>=`|`\|` / `^`|`x ^ 1 < 4` |`x < 4`|
  10
  11 ### Why is this bad?
  12 Not equally evil as [`bad_bit_mask`](#bad_bit_mask),
  13 but still a bit misleading, because the bit mask is ineffective.
  14
  15 ### Known problems
  16 False negatives: This lint will only match instances
  17 where we have figured out the math (which is for a power-of-two compared
  18 value). This means things like `x | 1 >= 7` (which would be better written
  19 as `x >= 6`) will not be reported (but bit masks like this are fairly
  20 uncommon).
  21
  22 ### Example
  23 ```
  24 if (x | 1 > 3) {  }
  25 ```