why lodash is used?

_.map, _.reduce, _.filter and _.forEach are frequently used functions when processing collections, and ES6 provides direct support for them:

But Lodash’s _.map is more powerful, in that it works on objects, has iteratee / predicate shorthands, lazy evaluation, guards against null parameter, and has better performance.

To iterate over an object in ES6, there’re several approaches:

With Lodash, there’s a unified _.forEach, for both array and object:

Although ES6 does provide forEach for the newly added Map type, it takes some effort to first convert an object into a Map:

To extract some property from an array of objects:

This can be more helpful when it comes to complex objects:

As we can see, Lodash not only provides conveniet shorthands, it also guards against undefined values. For _.filter, there’s also predicate shorthand. Here are some examples from Lodash documentation:

Here comes the fun part. Processing collections with chaining, lazy evaluation, along with short, easy-to-test functions, is quite popular these days. Most Lodash functions regarding collections can be chained easily. The following is a wordcount example:

ES6 introduces some useful syntaxes like destructuring, spread and arrow function, which can be used to replace a lot of Lodash functions. For instance:

For collection related operations, I prefer Lodash functions for they are more concise and can be chained; for functions that can be rewritten by arrow function, Lodash still seems more simple and clear. And according to some arguments in the references, the currying, operators and fp style from Lodash are far more useful in scenarios like function composition.

Are you tired of writing repetitive and verbose code in JavaScript? Well, let me introduce you to Lodash, a popular JavaScript library that can help you with that. Lodash provides a wide range of utility functions that makes working with arrays, objects, and functions a breeze. Its purpose is to make your life as a developer easier by providing a set of tools that simplify common tasks and help you write more readable and maintainable code.

One of the main things that Lodash addresses is the problem of boilerplate code. You know how sometimes you find yourself writing a lot of code just to perform simple tasks like sorting an array or finding an item in an object? Well, that’s where Lodash comes in. It provides a concise and consistent way of doing these tasks, which in turn improves your productivity as a developer.

For example, let’s say you have an array of users and you want to sort them by their last name. Without Lodash, you would have to write your own sorting function or use the native Array.sort method. But with Lodash, you can simply use the _.sortBy method and pass in the property to sort by.

One of the biggest benefits of using Lodash is the improved readability and maintainability of your code. Lodash’s functional programming approach encourages you to write code that is more declarative and less imperative. This means that instead of telling the computer how to do something step-by-step, you describe what you want it to do. This leads to code that is more self-explanatory and easier to understand.

A good example of this is the use of array methods. In plain JavaScript, you might use a for loop to iterate over an array and perform some operation on each item. But with Lodash, you can use methods like _.map, _.filter, and _.reduce to perform the same operation in a more declarative way. For example, let’s say you have an array of numbers and you want to double every number and return only the even numbers.

Another great reason to use Lodash is that it helps you to write cross-browser compatible code. As you may know, different browsers can have slight variations in their implementation of JavaScript and the DOM, which can lead to unexpected behavior or errors in your code. Lodash addresses this issue by providing a consistent API across all browsers, so you can be sure that your code will work the same way everywhere.

One example of this is the _.forEach method. In native JavaScript, you would use the forEach method to iterate over an array. But this method is not available in older versions of Internet Explorer. Lodash provides a consistent implementation of forEach method that works across all browsers, so you don’t have to worry about checking for browser compatibility or writing your own fallback function.

As you can see, the code is similar and you can use the same code on all browser with no problem.

Another example is the _.bind method, which is used to create a new function that has its this keyword bound to the provided value. This can be useful in situations where you want to pass a function as a callback, but need to ensure that the function’s this keyword is set to a specific value.

As you can see, using Lodash’s _.bind method is consistent across all browsers, and you can avoid any compatibility issues.

These are just a couple examples of how Lodash helps you write cross-browser compatible code, but there are many more utility functions that provide a consistent behavior across different browsers. With Lodash, you can be sure that your code will work the same way on all major browsers, giving you one less thing to worry about.

Not only does Lodash improve the readability and maintainability of your code, but it also has a number of internal optimizations that can help improve the performance of your code. Lodash’s functions are heavily optimized for speed and are designed to be as efficient as possible. This can be a great benefit, especially when working with large data sets or in performance-critical parts of your application.

One example of this is the use of the _.map method. In native JavaScript, the map method creates a new array, iterates over the original array, and applies a callback function to each item. This process creates a new array and can be slow if the original array is large. Lodash’s implementation of map uses an optimized algorithm that can be significantly faster, especially for large arrays.

Another example of this is the use of _.memoize. It is a method that will cache the result of a function and return it for the same set of inputs. This can be especially useful for expensive or time-consuming calculations where you want to avoid unnecessary re-computation.

These are just a few examples of how Lodash’s internal optimizations can help improve the performance of your code. By using Lodash, you can be sure that your code is running as efficiently as possible and you can optimize performance-critical parts of your application.

Another great reason to use Lodash is the large and active community behind it. Lodash is one of the most popular JavaScript libraries out there, with thousands of developers using it on a daily basis. This means that there is a wealth of knowledge and resources available to you as a developer, including extensive documentation, tutorials, and example code.

The large and active community also means that bugs and issues are quickly identified and addressed, and new features and improvements are constantly being added. Additionally, Lodash has a lot of contributors who work hard to make sure that it stays up-to-date with the latest JavaScript features and best practices.

Lodash also fits well into the JavaScript ecosystem, it can be used with other popular libraries and frameworks such as React, Angular, Vue, etc. For example, you can use it with React and use its utility functions to handle the state or props of your components.

While Lodash’s main focus is on providing a set of simple utility functions, it also provides a number of more advanced features that can be used to solve complex problems. These advanced features can be a powerful addition to your toolset and can help you write more efficient and maintainable code.

One example of this is the _.throttle and _.debounce functions. These functions are used to limit the rate at which a function can be called. For example, let’s say you have an autocomplete input and you want to send a request to the server every time the user types something but you also want to avoid sending too many requests. You can use _.debounce to send the request only after the user stops typing for a certain amount of time.

Another example of advanced feature is the _.curry function. This function can be used to create a new function that accepts some of its arguments and returns a new function that takes the remaining arguments. This can be useful for functional composition, and in scenarios where you want to pre-fill some of the arguments of a function.

Lodash is a popular javascript based library which provides 200+ functions to facilitate web development. It provides helper functions like map, filter, invoke as well as function binding, javascript templating, deep equality checks, creating indexes and so on.