#4 Built in Types in TS (Fundamentals of TS)

 There are different Types in TS which includes of JS and extends to:

number  string    boolean  null  undefined  object  any  unknown  never  enum  tuple

Example:

Let age : number= 18;

here number is the type for age.


ANY TYPE

If we write just age; it becomes an any type automatically because the type of the variable is not given.
The type "any" is mainly avoided because due to this, the purpose of a typescript loses its value.

While in arrays; Use;
let num : number[]= [1,2,3,4];


TUPLES Type

If we need to have an array with different types then tuples is used.
It can be used as:

Example:
let user:[number, string]=[2,"hello"]

It is usually used for  2 values of array. If the elements of an array exceeds the elements of type then there cause an error.

Example:

let user:[number, string]=[2,"hello",5]


ENUMS Type

If we need to add more than one constants, we use Enums. It makes the code easier to read and follow.

Example:

const enum Size{Small="s", Medium="M", Large="L"}

let User=Size.Small
(Value of user is s)

Here, we declare the type and value of constants inside the {} and can be used later on.

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