What is “accessor function”?

Question

In section 4.3.26 of the Standard ECMA-262 Edition:

Depending upon the form of the property the value may be represented either directly as a data value

Answer 1

A pair of accessor function are referring to getter and setter. You can indirectly access some value in your object, for example:

var person =
{
    get Name()
    {
        return this.name;
    },
    set Name(value)
    {
        this.name = value;
    }
};

person.Name = "X";
console.log(person.Name); // X