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Get the index of the object inside an array, matching a condition
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As of 2016, you're supposed to use Array.findIndex (an ES2015/ES6 standard) for this:
a = [
{prop1:"abc",prop2:"qwe"},
{prop1:"bnmb",prop2:"yutu"},
{prop1:"zxvz",prop2:"qwrq"}];
index = a.findIndex(x => x.prop2 ==="yutu");
console.log(index);
...
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...
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
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What are 'get' and 'set' in Swift?
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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...
How to validate an email address in JavaScript
Is there a regular expression to validate an email address in JavaScript?
95 Answers
9...
How can I trim leading and trailing white space?
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# Returns string without leading white space
trim.leading <- function (x) sub("^\\s+", "", x)
# Returns string without trailing white space
trim.trailing <- function (x) sub("\\s+$", "", x)
# Returns string without leading or trailing white space
trim <- function (x) gsub("^\\s+|\\s+$",...
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(...
Can you Run Xcode in Linux?
Can you run Xcode in Linux? Mac OS X was based on BSD Unix, so is it possible?
13 Answers
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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:
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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...