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Why '&&' and not '&'?
...hort-circuited, meaning that the evaluation is canceled as soon as the result is clear.
Example:
if(CanExecute() && CanSave())
{
}
If CanExecute returns false, the complete expression will be false, regardless of the return value of CanSave. Because of this, CanSave is not executed.
T...
Returning multiple objects in an R function [duplicate]
How can I return multiple objects in an R function? In Java, I would make a Class, maybe Person which has some private variables and encapsulates, maybe, height , age , etc.
...
Swift - Convert to absolute value
...on called abs(_:) method. abs(_:) has the following declaration:
func abs<T>(_ x: T) -> T where T : Comparable, T : SignedNumeric
Returns the absolute value of the given number.
The following code snippet shows how to use abs(_:) global function in order to get the absolute value on...
Fastest Way of Inserting in Entity Framework
...ntity, int count, int commitCount, bool recreateContext)
{
context.Set<Entity>().Add(entity);
if (count % commitCount == 0)
{
context.SaveChanges();
if (recreateContext)
{
context.Dispose();
context = new MyDbContext();
c...
How can I combine two commits into one commit? [duplicate]
...quantity of all your commits.
Open git bash and write: git rebase -i HEAD~<quantity of your commits> (i.e. git rebase -i HEAD~5)
In opened txt file change pick keyword to squash for all commits, except first commit (which is on the top). For top one change it to reword (which means you will pr...
What do hjust and vjust do when making a plot using ggplot?
... controls vertical justification.
An example should make this clear:
td <- expand.grid(
hjust=c(0, 0.5, 1),
vjust=c(0, 0.5, 1),
angle=c(0, 45, 90),
text="text"
)
ggplot(td, aes(x=hjust, y=vjust)) +
geom_point() +
geom_text(aes(label=text, angle=angle, hjust=hjust, vjus...
Clicking the back button twice to exit an activity
...(and accepted) answer on the question, which i think should have a better alternative such as;
What's wrong with measuring time passed and checking if TIME_INTERVAL miliseconds (say 2000) passed since the last back press. The following sample code uses System.currentTimeMillis(); to store the time ...
django syncdb and an updated model
...
From Django 1.7 onwards
Django has built in support for migrations - take a look at the documentation.
For Django 1.6 and earlier
Django doesn't support migrations out of the box. There is a pluggable app for Django that does exactly that though, and it works g...
How can I break an outer loop with PHP?
...
Use goto?
for ($i = 0, $j = 50; $i < 100; $i++)
{
while ($j--)
{
if ($j == 17)
goto end;
}
}
echo "i = $i";
end:
echo 'j hit 17';
share
|
...
Building big, immutable objects without using constructors having long parameter lists
...
In Scala 2.8, you could use named and default parameters as well as the copy method on a case class. Here's some example code:
case class Person(name: String, age: Int, children: List[Person] = List()) {
def addChild(p: Person) = copy(children = p :: this.children)...