Questions

How to disable text selection highlighting

For anchors that act like buttons (for example, the buttons on the sidebar of this Stack Overflow page titled , , and ) or tabs, is there a CSS standard way to disable the highlighting effect if the u...

How do I execute a program or call a system command?

How do I call an external command within Python as if I had typed it in a shell or command prompt?

How do I change the URI (URL) for a remote Git repository?

I have a repo (origin) on a USB key that I cloned on my hard drive (local). I moved "origin" to a NAS and successfully tested cloning it from here. I would like to know if I can change the URI of "ori...

24 Aug at 19:29

Which equals operator (== vs ===) should be used in JavaScript comparisons?

I'm using [JSLint](http://en.wikipedia.org/wiki/JSLint) to go through JavaScript, and it's returning many suggestions to replace `==` (two equals signs) with `===` (three equals signs) when doing thin...

Loop (for each) over an array in JavaScript

How can I loop through all the entries in an array using JavaScript?

How do I reset or revert a file to a specific revision?

How do I revert a modified file to its previous revision at a specific commit hash (which I determined via [git log](https://git-scm.com/docs/git-log) and [git diff](https://git-scm.com/docs/git-diff)...

8 Jul at 04:17

The definitive guide to form-based website authentication

> #### Moderator note: This question is not a good fit for our question and answer format with the [topicality rules](/help/on-topic) which currently apply for Stack Overflow. We normally use a "his...

How can I validate an email address in JavaScript?

I'd like to check if the user input is an email address in JavaScript, before sending it to a server or attempting to send an email to it, to prevent the most basic mistyping. How could I achieve this...

How can I safely create a directory (possibly including intermediate directories)?

I am writing a file using Python, and I want it to be placed in a specific path. How can I safely make sure that the path exists? That is: how can I check whether the folder exists, along with its par...

How do I push a new local branch to a remote Git repository and track it too?

How do I: 1. Create a local branch from another branch (via git branch or git checkout -b). 2. Push the local branch to the remote repository (i.e. publish), but make it trackable so that git pull an...

How do I replace all occurrences of a string in JavaScript?

Given a string: ``` s = "Test abc test test abc test test test abc test test abc"; ``` This seems to only remove the first occurrence of `abc` in the string above: ``` s = s.replace('abc', ''); ``` ...

24 Jul at 23:55

What is a plain English explanation of "Big O" notation?

I'd prefer as little formal definition as possible and simple mathematics.

How do I resolve merge conflicts in a Git repository?

How do I resolve merge conflicts in my Git repository?

How do I add an empty directory to a Git repository?

How do I add an empty directory (that contains no files) to a Git repository?

18 Jul at 18:41

What is the difference between "INNER JOIN" and "OUTER JOIN"?

Also, how do `LEFT OUTER JOIN`, `RIGHT OUTER JOIN`, and `FULL OUTER JOIN` fit in?

28 Aug at 04:26

Accessing the index in 'for' loops

How do I access the index while iterating over a sequence with a `for` loop? ``` xs = [8, 23, 45] for x in xs: print("item #{} = {}".format(index, x)) ``` Desired output: ``` item #1 = 8 item #2...

8 Aug at 00:51

How do I make a flat list out of a list of lists?

I have a list of lists like `[[1, 2, 3], [4, 5, 6], [7], [8, 9]]`. How can I flatten it to get `[1, 2, 3, 4, 5, 6, 7, 8, 9]`? --- [python list comprehensions; compressing a list of lists?](https://...

How do I exit Vim?

I am stuck and cannot escape. It says: ``` type :quit<Enter> to quit VIM ``` But when I type that it simply appears in the object body.

4 Jun at 11:47

Reference Guide: What does this symbol mean in PHP? (PHP Syntax)

### What is this? This is a collection of questions that come up every now and then about syntax in PHP. This is also a Community Wiki, so everyone is invited to participate in maintaining this list. ...

How do I squash my last N commits together?

How do I squash my last N commits together into one commit?

8 Jul at 04:55

How can I horizontally center an element?

How can I horizontally center a `<div>` within another `<div>` using CSS? ``` <div id="outer"> <div id="inner">Foo foo</div> </div> ```

10 Aug at 00:26

What's the difference between tilde(~) and caret(^) in package.json?

After I upgraded to the latest stable `node` and `npm`, I tried `npm install moment --save`. It saves the entry in the `package.json` with the caret `^` prefix. Previously, it was a tilde `~` prefix. ...

What is the difference between a URI, a URL, and a URN?

What is the difference between a [URL](http://en.wikipedia.org/wiki/Uniform_Resource_Locator), a [URI](http://en.wikipedia.org/wiki/Uniform_Resource_Identifier), and a [URN](http://en.wikipedia.org/wi...

6 Aug at 23:46

How to pass "Null" (a real surname!) to a SOAP web service in ActionScript 3

We have an employee whose surname is Null. Our employee lookup application is killed when that last name is used as the search term (which happens to be quite often now). The error received (thanks Fi...