JavaScript-Concepts/async_await.html at master · kipchirchiralb/JavaScript-Concepts · 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">
    <link rel="stylesheet" href="style.css">
    <title>Async Await</title>
</head>

<body>
    <h1>
        async await
    </h1>
    <script>
        //first, lets learn something abot a generator function. This is a special function.
        // what makes a generator function are the * and yield.
        //in below example, generatorFunc(), we are getting the data, pausing the function until we recieve the data and then doing something with the data.

        function* generatorFunc() {
            let data = getData()
            yield dataconsole.log(data)
        }

        //USING OUR CODE FROM PROMISES

        const hasMeeting = false;
        const meeting = new Promise((resolve, reject) => {
            if (hasMeeting) {
                const meetingDetails = {
                    name: "Marketing Meeting",
                    location: "Skype",
                    time: "1:00PM",
                    printMeetingDetails: () => {
                        console.log(`You have a ${meetingDetails.name} at ${meetingDetails.time}. Location: ${meetingDetails.location}`)
                    }
                }
                resolve(meetingDetails)
            } else {
                reject(new Error("ERROR: Meeting already/not scheduled"))
            }
        })

        const addToCalender = meetingDetails => {
            const calender = `${meetingDetails.name} is scheduled at ${meetingDetails.time} on ${meetingDetails.location}`

            return Promise.resolve(calender)
        }

        async function myMeeting() {
            try {
                const meetingDetails = await meeting
                const message = await addToCalender(meetingDetails)
                console.log(message)
            } catch (err) {
                console.log(err.message)
            }
        }
        myMeeting()

        // myMeeting().catch(err => console.log(err.message)) //this is an alternative for try catch, since you dont wanna do this for all function calls in a large code.
    </script>
</body>

</html>