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How to validate an email address in JavaScript
Is there a regular expression to validate an email address in JavaScript?
95 Answers
9...
How to select the row with the maximum value in each group
...iple observations for each subject I want to take a subset with only the maximum data value for each record. For example, with a following dataset:
...
What are type lambdas in Scala and what are their benefits?
...he time when you are working with higher-kinded types.
Consider a simple example of defining a monad for the right projection of Either[A, B]. The monad typeclass looks like this:
trait Monad[M[_]] {
def point[A](a: A): M[A]
def bind[A, B](m: M[A])(f: A => M[B]): M[B]
}
Now, Either is a t...
What are 'get' and 'set' in Swift?
...
That's actually explained right before the code:
In addition to simple properties that are stored, properties can have a getter and a setter.
class EquilateralTriangle: NamedShape {
...
When some other class wants to get that perimete...
Is it possible to override JavaScript's toString() function to provide meaningful output for debuggi
...
You can override toString in Javascript as well. See example:
function Foo() {}
// toString override added to prototype of Foo class
Foo.prototype.toString = function() {
return "[object Foo]";
}
var f = new Foo();
console.log("" + f); // console displays [object Foo]
...
How to determine whether a given Linux is 32 bit or 64 bit?
...
Try uname -m. Which is short of uname --machine and it outputs:
x86_64 ==> 64-bit kernel
i686 ==> 32-bit kernel
Otherwise, not for the Linux kernel, but for the CPU, you type:
cat /proc/cpuinfo
or:
grep flags /proc/cpuinfo
Under "flags" parameter, you will see various va...
How do I make my GUI behave well when Windows font scaling is greater than 100%
...ere are problems in a VCL application, every time something has been set pixelwise.
4 Answers
...
Drawing a line/path on Google Maps
...otected boolean isRouteDisplayed() {
return false;
}
class MyOverlay extends Overlay{
public MyOverlay(){
}
public void draw(Canvas canvas, MapView mapv, boolean shadow){
super.draw(canvas, mapv, shadow);
Paint mPaint = new Paint();
mPaint.setDither(...
How do I run msbuild from the command line using Windows SDK 7.1?
...ld in Command Prompt, you simply have to add the directory of the msbuild.exe install on your machine to the PATH environment variable.
You can access the environment variables by:
Right clicking on Computer
Click Properties
Then click Advanced system settings on the left navigation bar
On the next...
How do I get a substring of a string in Python?
...
>>> x = "Hello World!"
>>> x[2:]
'llo World!'
>>> x[:2]
'He'
>>> x[:-2]
'Hello Worl'
>>> x[-2:]
'd!'
>>> x[2:-2]
'llo Worl'
Python calls this concept "slicing" and it works on more t...