JavaScript/PromiseIntro.html at master · vishal-vaish/JavaScript · GitHub

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<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>

</body>
</html>
<script>
    //How to we solve inversion of control problem

    //Promises

    //Alternative to Callback

    const cart=["shoes","pants","kurta"];

    const orderId=createOrder();
    console.log(5);
    // proceedToPayment();

    //We will make createOrder function return a promise
    //We will store that promise in a variable

    //Promise is nothing but an empty object with some data in it.
    //{data:}

    //createOrder function is async and we don't know how much time will it take to execute
    //{data:undefined}

    //After Finishing Exection
    //{data:orderId}

    orderId.then(()=>{
        //here we come to know that function has completed the execution
        proceedToPayment();
    })
</script>