October 2006
Beginner to intermediate
352 pages
9h 33m
English
Content preview from Learning JavaScriptBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Questions
Of the following identifiers, which are valid, which are not, and why?
$someVariable _someVariable 1Variable some_variable somèvariable function .someVariable some*variable
Convert the following identifiers using the conventions outlined in the first section of the chapter:
var some_month; function theMonth // function to return current month current-month // a constant var summer_month; // an array of summer months MyLibrary-afunction // a function from a JavaScript package
Is the following string literal valid? If not, how would you fix it?
var someString = ‘Who once said, “Only two things are infinite, the universe and human stupidity, and I’m not sure about the former.”’
Given a number, 432.54, what JavaScript returns the integer component of the number, and then finds the hexadecimal and octal conversion?
You create a JavaScript function in a library that can be used by other applications. A parameter,
someMonth, is passed to the function. How would you determine whether it’s null or undefined?
Answers are provided in the appendix.
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I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.