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How exactly does a generator comprehension work?
... generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one by one.
>>> my_list = [1, 3, 5, 9, 2, 6]
>>> filtered_list = [item for item in my_list i...
Does Dart support enumerations?
...ase Fruit.apple:
print('it is an apple');
break;
}
// get all the values of the enums
for (List<Fruit> value in Fruit.values) {
print(value);
}
// get the second value
print(Fruit.values[1]);
}
The old approach before 1.8:
class Fruit {
static const APPLE =...
Is there a function to make a copy of a PHP array to another?
...ewLarsson raises a point in the comments below. PHP has a special feature called "references". They are somewhat similar to pointers in languages like C/C++, but not quite the same. If your array contains references, then while the array itself is passed by copy, the references will still resolve to...
A semantics for Bash scripts?
...patchwork together little scripts that appear to work. However, I don't really know what's going on, and I was hoping for a more formal introduction to Bash as a programming language. For example: What is the evaluation order? what are the scoping rules? What is the typing discipline, e.g. is ever...
How do I get NuGet to install/update all the packages in the packages.config?
...e are packages.config file for each project. How do I get NuGet to install/update all the packages needed? Does this need to be done via command line for each project?
...
Are C# events synchronous?
...stions:
Raising an event does block the thread if the event handlers are all implemented synchronously.
The event handlers are executed sequentially, one after another, in the order they are subscribed to the event.
I too was curious about the internal mechanism of event and its related operatio...
How to prevent IFRAME from redirecting top-level window
...
iFrames do allow cross-domain communication, though, using postMessage. This isn't a security risk, but someone might care to know that this capability exists when they see your comment. :)
– coreyward
...
Is explicitly closing files important?
In Python, if you either open a file without calling close() , or close the file but not using try - finally or the " with " statement, is this a problem? Or does it suffice as a coding practice to rely on the Python garbage-collection to close all files? For example, if one does this:
...
Deadly CORS when http://localhost is the origin
...lija's comment is correct, adding these headers to localhost will not magically give you access to all other sites. It's the remote site that needs to be served with these headers.
– Rob W
Mar 22 '14 at 22:59
...
Installing Java on OS X 10.9 (Mavericks)
I have installed the JDK on Mac OS X v10.8 (Mountain Lion). When I upgraded it to Mac OS X v10.9 (Mavericks) and ran java -version in the terminal, it showed:
...