Npm Moment Libraries

When are moment libraries useful?

Moment libraries such as those available via the npm package manager become useful when working with dates and times in JavaScript. JavaScript's built-in date object does not always suffice in real-world scenarios. This is where the moment libraries come into the picture.

Moment libraries offer a more extensive feature set and provide robust functionalities. They are particularly handy in the following scenarios:

• Manipulating dates and times.
• Validating dates.
• Parsing strings into date objects.
• Comprehensive formatting options for displaying dates and times according to various locales.
• Calculations involving dates such as the difference between two dates.

What functionalities do moment libraries usually have?

Moment libraries are designed to bridge the gap where JavaScript's native Date object falls short. Here are some of the many features offered by such libraries:

• Date Parsing: Moment libraries provide reliable ways of parsing date strings into date objects.

• Date Manipulation: Moment libraries offer flexible tools for manipulating dates and times. For example, you can add or subtract years, months, weeks, days, hours, minutes, seconds, and even milliseconds.

• Date Validation: Moment libraries allow validation of date strings before converting them into date objects.

• Date Difference: Moment libraries have a method for calculating the difference between two dates.

• Timezone Support: Moment libraries acknowledge the importance of time zones, providing you the ability to retrieve the timezone offset and use it in all your operations.

• Formatting and Displaying: One of the killer features of moment libraries is its formatting feature. This provides extensive customization for displaying date and time in various ways which can adapt to user's locale.

Gotchas/Pitfalls to look out for

Though Moment libraries are extensively used and appreciated, they come with their set of potential pitfalls and concerns.

• Size: Moment libraries are quite large which could be a concern for web performance. Mindful implementation of code splitting, tree-shaking or opting for lighter alternatives might be considered in performance-intensive applications.

• Immutable Objects: Unlike native JavaScript Date objects, moment objects are mutable which might lead to unexpected results. It's always recommended to clone the original moment object before making any manipulations.

• Overhead: The rich feature-set of moment libraries comes with a cost - it might be overkill for simple date operations. Understanding the exact requirements and choosing a simpler, lightweight library instead could be more efficient.

• Deprecation: It's also essential to note that as of Sept 2020, Moment.js (a popular moment library) has been deprecated meaning it is no longer being actively developed or maintained. It is recommended to only use it on existing projects and opt for newer, lighter, and faster alternatives for new projects.