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import * as React from 'react';

interface IStateComponent{
  time:Date();
}

interface IPropComponent{
  name:string;
}

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//this is TypeScript declaration
enum Suit {
  Club, Diamond, Heart, Spade
}

// in JavaScript like this
var Suit;
(function(Suit){
  Suit[Suit["Club"]=0]="Club";
  Suit[Suit["Diamond"]=1]="Diamond";

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// It is the worht mentioning that Putting I+your interface name is best practice
// we define our Date shape object
interface IDate {
  year:number;
  month:number;
  day:number;
}

interface IPerson{
  name:string;

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function registerUser(user:{name:string,age:number,gender:string}){
  .... /// some function implementation
}

// let's define some shapes
//ok 
let person1={
  name:'Hojiakbar',
  age:22,
  gender:'male'

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let input=document.querySelector('input#form_age_field') as HTMLInputElement

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let age:number=22 // ":" this is called type annotation 

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let age=22 // TypeScript smart enough to know this is number
age='22' // This is not ok string type is not assignible to a type number