Question

I am learning jQuery from book “Learning jQuery”, and found part of code that don’t understand.

There is part of JSON:

[
    {
        "term": "BACCHUS",
        "part": "n.",
        "definition": "A convenient deity invented by the...",
        "quote": [
            "Is public worship, then, a sin,",
            "That for devotions paid to Bacchus",
            "The lictors dare to run us in,",
            "And resolutely thump and whack us?"
        ],
        "author": "Jorace"
    },
    {
        "term": "BACKBITE",
        "part": "v.t.",
        "definition": "To speak of a man as you find him when..."
    },
    {
        "term": "BEARD",
        "part": "n.",
        "definition": "The hair that is commonly cut off by..."
    },

Here is jQuery code:

$(document).ready(function() {
    $('#letter-b a').click(function() {
        $.getJSON('b.json', function(data) {
            $('#dictionary').empty();
            $.each(data, function(entryIndex, entry) {
                var html = '<div class="entry">';
                html += '<h3 class="term">' + entry['term'] + '</h3>';
                html += '<div class="part">' + entry['part'] + '</div>';
                html += '<div class="definition">';
                html += entry['definition'];
                if (entry['quote']) {
                    html += '<div class="quote">';
                    $.each(entry['quote'], function(lineIndex, line) {
                        html += '<div class="quote-line">' + line + '</div>';

Can someone explain me meaning of this line:

if (entry['quote'])

P.S. I tried to search stackoverflow and Google but couldn’t found explanation for this.

Answer 1

All if(entry[‘quote’]) is doing is checking to see if this key exists in the entry structure.