Rule: function-constructor

Prevents using the built-in Function constructor.

Rationale

Calling the constructor directly is similar to eval, which is a symptom of design issues. String inputs don’t receive type checking and can cause performance issues, particularly when dynamically created.

If you need to dynamically create functions, use “factory” functions that themselves return functions.

Config

Not configurable.

Config examples

"function-constructor": true

Schema

null

Code examples:

"rules": { "function-constructor": true }

let doesNothing = () => {};

let doesNothing = new Function();

"rules": { "function-constructor": true }

let addNumbers = (a, b) => a + b;

let addNumbers = new Function("a", "b", "return a + b");