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no-bitwise

docs/src/rules/no-bitwise.md

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Original Source

The use of bitwise operators in JavaScript is very rare and often & or | is simply a mistyped && or ||, which will lead to unexpected behavior.

js
const x = y | z;

Rule Details

This rule disallows bitwise operators.

Examples of incorrect code for this rule:

::: incorrect

js
/*eslint no-bitwise: "error"*/

let x = y | z;

const x1 = y & z;

const x2 = y ^ z;

const x3 = ~ z;

const x4 = y << z;

const x5 = y >> z;

const x6 = y >>> z;

x |= y;

x &= y;

x ^= y;

x <<= y;

x >>= y;

x >>>= y;

:::

Examples of correct code for this rule:

::: correct

js
/*eslint no-bitwise: "error"*/

let x = y || z;

const x1 = y && z;

const x2 = y > z;

const x3 = y < z;

x += y;

:::

Options

This rule has an object option:

  • "allow": Allows a list of bitwise operators to be used as exceptions.
  • "int32Hint": Allows the use of bitwise OR in |0 pattern for type casting.

allow

Examples of correct code for this rule with the { "allow": ["~"] } option:

::: correct

js
/*eslint no-bitwise: ["error", { "allow": ["~"] }] */

~[1,2,3].indexOf(1) === -1;

:::

int32Hint

Examples of correct code for this rule with the { "int32Hint": true } option:

::: correct

js
/*eslint no-bitwise: ["error", { "int32Hint": true }] */

const b = a|0;

:::