unnecessaryUseStricts

Reports unnecessary "use strict" directives in ES modules and classes.

✅ This rule is included in the ts logical presets.

ECMAScript modules and class bodies are automatically in strict mode. The "use strict" directive has no effect in these contexts and is redundant.

This rule reports on "use strict" directives that can be safely removed.

Examples

❌ Incorrect

"use strict";

export function calculate(value: number) {
  return value * 2;
}

export class Calculator {
  add(a: number, b: number) {
    return a + b;
  }
}

✅ Correct

export function calculate(value: number) {
  return value * 2;
}

export class Calculator {
  add(a: number, b: number) {
    return a + b;
  }
}

Options

This rule is not configurable.

When Not To Use It

If you are working in a JavaScript environment with non-standard semantics, or otherwise have tooling that requires you to use seemingly redundant "use strict" directives, this rule might not be for you.

Further Reading

• MDN: Strict mode
• MDN: JavaScript modules

Equivalents in Other Linters

• Biome: noRedundantUseStrict