Promises - Fetch Method

    let url = "http://jsonplaceholder.typicode.com/comments?postId=42";
    
    fetch(url)
    .then(response => response.json() )
    .then(data => {
        let str = JSON.stringify(data, null, '\t');
        //output the string version of the JSON data as preformatted text
        //document.querySelector('#output pre').textContent = str;
        //output the postId from the first object in the data array
        document.querySelector('#output').textContent = data[0].postId;
    })
    .catch(err => {
        let nm = err.name;      //Error Type
        let msg = err.message;  //The error message
        alert(`CATCH: ${nm} ${msg}`);
    });