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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.

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Written By:
Saurabh Joshi

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