We can dot-chain our way to great success with an instance of Maybe, but there are probably cases where you need to apply the same series of transformations against different Maybes. In this lesson, we’ll look at some point-free versions of some comm…

You probably have functions that aren’t equipped to accept a Maybe as an argument. And in most cases, altering functions to accept a specific container type isn’t desirable. You could use map, passing in your function, or you could “lift” your functi…

In this lesson, we’ll create a safe function that gives us a flexible way to create Maybes based on a value and a predicate function that we supply. We’ll verify its behavior with values that satisfy the predicate, and values that do not. We can writ…

Functions are first class in JavaScript. This means we can treat a function like any other data. This also means we can end up with a function as the wrapped value in a Maybe. The Maybe type gives us the ability to apply that wrapped function to othe…

The alt method allows us to recover from a nothing with a default Maybe, but sometimes our recovery efforts might need to enlist some logic to recover properly. In this lesson, we’ll see how we can use the coalesce method on the Maybe to recover from…

In this lesson, we’ll use a Maybe to safely operate on properties of an object that could be undefined. We’ll use our initial code as the basis for a prop utility function that can be reused with different objects and various property names. Instead…

1. 介绍 第一眼看到ES6新增加的 arrow function 时,感觉非常像 lambda 表达式. 那么arrow function是干什么的呢?可以看作为匿名函数的简写方式. 如: var addition = function(a, b) { return a + b }; // 等同 var addition = (a, b) => { return a + b }; 2. 语法 arrow functions(箭头函数)主要有以下4种语法: // 1)基本 (param1, pa…

Once we’re using Maybes throughout our code, it stands to reason that at some point we’ll get a Maybe and want to continue applying transformations. We might get a Nothing and want to perform those same transformations on some default value. In this…

In this lesson, we’ll get started with the Maybe type. We’ll look at the underlying Just and Nothing types and create a simple utility function to create a Maybe from a value. Then we’ll see how we can apply functions to values and skip invocation fo…

if-statements can add serious complexity and beg for refactoring. You can use polymorphic functions to simplify your ifs and dynamically call the appropriate method. For example you have the code like: function charge(){ if(this.moive.type==="regular…