Thought I would write a quick post on semver the nodejs npm package that helps with the semver.org Semantic Versioning standard for version numbers. If you are planing to make a serious nodejs project it is a good standard to at least be somewhat aware of. For many not so serious projects I still conform to it as to many other developers. Even if you do not wish to conform to the standard there are still many concerns when it comes to making a project that involves a public API of some kind. Making any changes to a public API might result in code breaking in any and all projects that depend on it for example. So learning a thing or two about the standard, can help with concerns that will arise as a project is maintained.

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In javaScript there is the eval function that can be used to execute a string representation of some javaScript code. It is generally something to be avoided for various reasons, and it it really must be used should be used with care. In projects where the string value is passed from user input there is the risk of introducing security problems if the input is not sanitized. In general if you can find a way to do what you want to do with eval by some other means do that instead.

There are other ways of evaluating javaScript code that involve other aspects of native javaScript such as the function constructor, as well as user space modules like jsdom. There is also ways or making parsers that will act as a way to make my own domain specific language rather than using eval to run javaScript code in string format. However that is a matter for a whole other post on something other than js eval.

The eval function should not be used if it can be avoided, the use of the eval function can slow things down, and can also open up some security concerns. I can not say that I use eval often, and even when I am in a situation in which I seems like I need to use it I do what I can to look for other options. Still this is a post on js eval, so then this will be a post on some of the ins and outs of the js eval function for what it is worth.

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So the regular number type in javaScript has some limitations when it comes to working with very large numbers beyond that of the max safe integer. Beyond that when it comes to adding a low number such as one to a number at, and beyond max safe integer you might end up with the same number as the result of the expression. So then it goes without saying that after that range, certain operations can not be preformed without a loss of precision, thus the name Max Safe Integer.

To get around this limitation with javaScript numbers in the past, a library would have to be used that involves representing a number with a string, and then have custom method that is part of this library for preforming operations with these types of objects was a way to work with big numbers in a project. For a long time the use of an external library was required when it comes to working with large numbers beyond max safe integer, and preserving high precision when preforming operations. These modules still work just fine, and often might still prove to be a better choice over a native solution, but as of late yes there is a native solution for this now.

So with that said in modern browsers, and node 10.4.x+ there is now the BigInt Object that now provides high precision math functionality in native javaScript by itself without the introduction of an external module. As of this writing the BigInt object is still not well supported so you might still want to use a library for that reason, but in time such libraries will no longer be needed for this because of this native support. So lets look at a few quick examples of the native bigInt object and what is has to provided in platforms that support it.

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When working out some kind of interface for a client side javaScript project select tags are often used to give the user a range of options to choose from with additional option tags nested in a select tag. In other words the use of select tags along with option tags will result in a drop down menu of sorts, where one option might serve as a default of sorts along with at least one other option.

There might be other ways of doing so that involve a canvas element, and some additional javaScript code to make some kind of more artful solution for selecting something from a range of options. However the select tag is a nice quick solution for doing something to that effect with other html elements outside of that of the canvas element, and the 2d drawing context. Making something from the ground up for this will often prove to be a bit more flashy, and allow for a greater deal of control when it comes to selecting things, but it will also prove to be far more time consuming also.

A select tag or select element consists of a select tag and then a few nested option tags for each option in the selection tag. There are a few things to be aware of when it comes to using this kind of html element in a project when it comes to making it actually do something with javaScript. There are events such as the on change event, and additional html attributes that come into play also. So lets look at some select element examples, and also touch base one other related topics when it comes to events, and other elements and attributes that will come into play when working with such an element.

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In lodash there is the _.isEmpty method than can be used to find if a collection object is empty or not. This is not to be confused with other possible values that might be considered empty such as null, a false boolean value and so forth. There are also a number of ways to go about doing the same when it comes to working with just plain old native javaScript in addition to using the lodash is empty method.

So this makes the lodash is empty method yet another one of those kinds of methods that make me scratch my head wondering if lodash is something that a developer should be bothering with at all even. I have to admit whenever I do use lodash in a project it is to use just one or two methods that are in there, it often makes more sense to install methods one at a time rather than bothering with the whole utility library, but never the less lets take a look at this one and maybe some vanilla javaScript alternatives to it also while we are at it.

In any case in this post I will be taking a quick look at the lodash is empty method, and also some vanilla javaScript code that also does what the lodash is empty method is for.

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