no-bitwise

Disallow bitwise operators

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

const x = y | z;
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Rule Details

This rule disallows bitwise operators.

Examples of incorrect code for this rule:

/*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;
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Examples of correct code for this rule:

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

let x = y || z;

const x1 = y && z;

const x2 = y > z;

const x3 = y < z;

x += y;
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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:

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

~[1,2,3].indexOf(1) === -1;
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int32Hint

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

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

const b = a|0;
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Version

This rule was introduced in ESLint v0.0.2.

Resources

• Rule source
• Tests source