Arrow functions cannot be bound

• USELESS_ARROW_FUNC_BIND
• Code Quality
• Low
• es6

This rule applies when an arrow function is bound.

Arrow functions are always bound with the this object of the context at which the function is defined, and it cannot be changed.
Therefore, the attempt to bind arrow functions with calling bind() or call() has no effect.

Note: Not applied when the first argument of bind() is a dummy value like undefined, null, or {} because copying a function value may be intended.

Noncompliant Code Example

function Adder(base) {
    this.base = base;

    var add = (a) => {
        return this.base + a;
    };

    this.addBase = function (baseObj, a) {
        return add.call(baseObj, a); // USELESS_ARROW_FUNC_BIND alarm because the bound function 'add' is an arrow function.
    };
}

var adder = new Adder(1);
adder.addBase({ base: 2 }, 2); // Return value is 3

Compliant Code Example

function Adder(base) {
    this.base = base;

    var add = (a) => {
        return this.base + a;
    };

    this.addBase = function (baseObj, a) {
        this.base = baseObj.base;
        return add(a);
    };
}

var adder = new Adder(1);
adder.addBase({ base: 2 }, 2); // Return value is 4

Version

This rule was introduced in DeepScan 1.11.0-beta.

See

• Arrow functions