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JavaScript: xtype.js


This article is about the weirdness  of javascript and how to handle it by xtype.js.
So I am talking about weirdness in terms of types in JS.
The typeof operator returns the type in a string format of the unevaluated operand.
For example:
typeof({}) => will return 'object'

typeof(5) => will return 'number'

Well, this is not weird.
Let me show you something weird,

typeof(new Date())  => will return 'object'
typeof([‘Max’, ‘Carl’, ‘Tom’])  => will return 'object'
typeof(/ab+c/i) => will return 'object'       

So it may create problems when you have to do some kind of validations on a type basis.
But with xtype.js there is a reliable solution for it.

Npm Available:
npm install xtype

Also, you can use it in the browser by downloading it.

Let's have a look at how we can solve this type of validations reliably.

xtype.type(new Date())                 // date
xtype.type([‘Max’, ‘Carl’, ‘Tom’])     // array
xtype.type({ name: ‘Max’, age: 20 })   // object
xtype.type(/ab+c/i)                    // regexp
xtype.type(new Error(‘Error’))         // error

Also, by passing the value directly we can get more details about type.
xtype.type(-1.1)                       // number

// more details please:
xtype(-1.1)                            // negative_float
xtype(1)                               // positive_integer
xtype('')                              // empty_string
xtype('  ')                            // whitespace
xtype(["Max", "Carl"])                 // multi_elem_array
xtype(["Max"])                         // single_elem_array

Isn't that amazing?
And it’s only 7kB in size.
There is so much more to discover in the official documentation.

If you found this article helpful, please share your feedback in the comments section.
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Written By:
Saurabh Joshi

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