【英文】JS高阶函数

Preface

Notes on learning advanced functions in JS

If a function takes a function as a parameter (such as a callback function), then this function is a higher-order function. If a function’s return value is a function (such as a closure), then this function is a higher-order function.

Callback Function

function fn(callback) {
    callback && callback();
}

fn(function() {
    ...
});

Closure

• A function that can access the local variables of another function is called a closure.
• The main purpose of a closure is to extend the scope of local variables.

function father() {
    var variableName = value;
    function son() { // closure
        variableName = value;
    };
    return son;
}

var son = father();

Small Closure

• Immediately invoked function expressions (IIFE) are called small closures because the parameters passed to the IIFE can be used inside the IIFE.

(function(i) {
    console.log(i);
})(i);

Completion

References

Bilibili - HEIMA Front-End