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JavaScript, Node.js: is Array.forEach asynchronous?
...k at the specification of the algorithm.
However a maybe easier to understand implementation is given on MDN:
if (!Array.prototype.forEach)
{
Array.prototype.forEach = function(fun /*, thisp */)
{
"use strict";
if (this === void 0 || this === null)
throw new TypeError();
va...
How do I check for null values in JavaScript?
... !user){
Which will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks agains...
Can a class extend both a class and implement an Interface
Can a class extend both an interface and another class in PHP?
Basically I want to do this:
3 Answers
...
How do you get centered content using Twitter Bootstrap?
I'm trying to follow a very basic example. Using the starter page and the grid system , I was hoping the following:
23 An...
How do I fetch lines before/after the grep result in bash?
...
You can use the -B and -A to print lines before and after the match.
grep -i -B 10 'error' data
Will print the 10 lines before the match, including the matching line itself.
...
Is there a list of screen resolutions for all Android based phones and tablets? [closed]
If not, is there a list of screen resolutions for the most popular Android phones and tablets.
7 Answers
...
Converting ISO 8601-compliant String to java.util.Date
...Unfortunately, the time zone formats available to SimpleDateFormat (Java 6 and earlier) are not ISO 8601 compliant. SimpleDateFormat understands time zone strings like "GMT+01:00" or "+0100", the latter according to RFC # 822.
Even if Java 7 added support for time zone descriptors according to ISO ...
git discard all changes and pull from upstream
How do I fetch upstream repo and make it replace master? I only have one branch on my repo, which is master, and I completely messed it up, so I basically need to start over from the upstream. I think init will do the job, but is there an easier way?
...
How to turn on line numbers in IDLE?
...on 3.8 or newer:
To show line numbers in the current window, go to Options and click Show Line Numbers.
To show them automatically, go to Options > Configure IDLE > General and check the Show line numbers in new windows box.
Version 3.7 or older:
Unfortunately there is not an option to display...
How to control the line spacing in UILabel
...when put in multiple lines in a UILabel ? We can set the frame, font size and number of lines. I want to reduce the gap between the two lines in that label.
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