No error , No gain

I saw some code that seems to use an operator I don't recognize, in the form of two exclamation points, like so: !!. Can someone please tell me what this operator does? The context in which I saw this was, this.vertical = vertical !== undefined ? !!vertical : this.vertical; Converts Object to boolean. If it was falsey (e.g. 0, null, undefined, etc.), it will be false, otherwise, true. !oObject /..

In an HTML table, the cellpadding and cellspacing can be set like this: How can the same be accomplished using CSS? Basics For controlling "cellpadding" in CSS, you can simply use padding on table cells. E.g. for 10px of "cellpadding": td { padding: 10px; } For "cellspacing", you can apply the border-spacing CSS property to your table. E.g. for 10px of "cellspacing": table { border-spacing: 10px..

All I want is to get the website URL. Not the URL as taken from a link. On the page loading I need to be able to grab the full, current URL of the website and set it as a variable to do with as I please. Use: window.location.href As noted in the comments, the line below works, but it is bugged for Firefox. document.URL See URL of type DOMString, readonly. Community Wiki URL Info Access JavaScrip..

I am looking for a JavaScript array insert method, in the style of: arr.insert(index, item) Preferably in jQuery, but any JavaScript implementation will do at this point. You want the splice function on the native array object. arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an arr..

I am a bit puzzled by the following code: d = {'x': 1, 'y': 2, 'z': 3} for key in d: print (key, 'corresponds to', d[key]) What I don't understand is the key portion. How does Python recognize that it needs only to read the key from the dictionary? Is key a special word in Python? Or is it simply a variable? key is just a variable name. for key in d: will simply loop over the keys in the diction..

I started some work on a new feature and after coding for a bit, I decided this feature should be on its own branch. How do I move the existing uncommitted changes to a new branch and reset my current one? I want to reset my current branch while preserving existing work on the new feature. Update 2020 / Git 2.23 Git 2.23 adds the new switch subcommand in an attempt to clear some of the confusion..

Over the years I have slowly developed a regular expression that validates most email addresses correctly, assuming they don't use an IP address as the server part. I use it in several PHP programs, and it works most of the time. However, from time to time I get contacted by someone that is having trouble with a site that uses it, and I end up having to make some adjustment (most recently I real..

Want to improve this post? Provide detailed answers to this question, including citations and an explanation of why your answer is correct. Answers without enough detail may be edited or deleted. I was looking at the new APIs introduced in Android 4.2. While looking at the UserManager class I came across the following method: public boolean isUserAGoat() Used to determine whether the user making..

My initial commit contained some log files. I've added *log to my .gitignore, and now I want to remove the log files from my repository. git rm mylogfile.log will remove a file from the repository, but will also remove it from the local file system. How can I remove this file from the repo without deleting my local copy of the file? From the man file: When --cached is given, the staged content h..

How can I create or use a global variable in a function? If I create a global variable in one function, how can I use that global variable in another function? Do I need to store the global variable in a local variable of the function which needs its access? You can use a global variable within other functions by declaring it as global within each function that assigns a value to it: globvar = 0..