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Is it possible to allow didSet to be called during initialization in Swift?
...someProperty as type: AnyObject! (an implicitly
unwrapped optional), you allow self to fully initialize without
someProperty being set. When you call
setSomeProperty(someProperty) you're calling an equivalent of
self.setSomeProperty(someProperty). Normally you wouldn't be able to
do this b...
When should I use @classmethod and when def method(self)?
...fine functions in classes. The author seems to use them both very intentionally. The first one is one I myself use a lot:
3...
Cannot refer to a non-final variable inside an inner class defined in a different method
...have been cleaned up.
By making lastPrice and price final, they are not really variables anymore, but constants. The compiler can then just replace the use of lastPrice and price in the anonymous class with the values of the constants (at compile time, of course), and you won't have the problem wit...
Blocks and yields in Ruby
...trary segments of code.
When a method expects a block, it invokes it by calling the yield function.
This is very handy, for instance, to iterate over a list or to provide a custom algorithm.
Take the following example:
I'm going to define a Person class initialized with a name, and provide a ...
Can an AngularJS controller inherit from another controller in the same module?
... the child controller injects the scope of the parent controller my $scope.AllMembers array get's populated twice as the parent controller causes it to run, then the child controller causes it to run again. Is there any way to prevent that?
– Ryan Mann
Jul 15 ...
What is the difference between Class.getResource() and ClassLoader.getResource()?
...esource paths are always deemed to be absolute.
So the following are basically equivalent:
foo.bar.Baz.class.getResource("xyz.txt");
foo.bar.Baz.class.getClassLoader().getResource("foo/bar/xyz.txt");
And so are these (but they're different from the above):
foo.bar.Baz.class.getResource("/data/x...
Co-variant array conversion from x to y may cause run-time exception
...js[0] = new Foo(); // again legal, with runtime exception
In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
Ruby class instance variable vs. class variable
...n store something common to that class without having sub-classes automatically also get them (and vice-versa). With class variables, you have the convenience of not having to write self.class from an instance object, and (when desirable) you also get automatic sharing throughout the class hierarchy...
Checking if an instance's class implements an interface?
...onstruct() is:
public function __construct() {
$tmp = array(
'foo' => 'bar',
'this' => 'that'
);
$in = in_array('those', $tmp);
}
These tests are based on this simple code.
share
...
How can I declare and use Boolean variables in a shell script?
......
if [ "$the_world_is_flat" = true ] ; then
echo 'Be careful not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_flat=true
# ...do something interesting...
if $the_world_is_flat ; then
echo 'Be careful not to fall off!'
fi
From: Usi...