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await vs Task.Wait - Deadlock?
...
Wait and await - while similar conceptually - are actually completely different.
Wait will synchronously block until the task completes. So the current thread is literally blocked waiting for the task to complete. As a general rule, you should use "async all the ...
Super-simple example of C# observer/observable with delegates
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The observer pattern is usually implemented with events.
Here's an example:
using System;
class Observable
{
public event EventHandler SomethingHappened;
public void DoSomething() =>
SomethingHappened?.Invoke(this, EventArgs.Empt...
M_PI works with math.h but not with cmath in Visual Studio
...) and suddenly it compile perfectly.
Try moving it higher up the page. Totally unsure as to why this would cause issues though.
Edit: Figured it out. The #include <math.h> occurs within cmath's header guards. This means that something higher up the list of #includes is including cmath with...
What does curly brackets in the `var { … } = …` statements do?
...h JavaScript 1.7 features. The first one is block-level variables:
let allows you to declare variables, limiting its scope to the block, statement, or expression on which it is used. This is unlike the var keyword, which defines a variable globally, or locally to an entire function regardless of...
Reading a huge .csv file
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You are reading all rows into a list, then processing that list. Don't do that.
Process your rows as you produce them. If you need to filter the data first, use a generator function:
import csv
def getstuff(filename, criterion):
with ...
Dispelling the UIImage imageNamed: FUD
...ister thread on the Apple Dev Forums received some better traffic. Specifically Rincewind added some authority.
There are issues in iPhone OS 2.x where the imageNamed: cache would not be cleared, even after a memory warning. At the same time +imageNamed: has gotten a lot of use not for the cache, b...
What does jQuery.fn mean?
...roperty.
The jQuery identifier (or $) is just a constructor function, and all instances created with it, inherit from the constructor's prototype.
A simple constructor function:
function Test() {
this.a = 'a';
}
Test.prototype.b = 'b';
var test = new Test();
test.a; // "a", own property
test....
Which is better, number(x) or parseFloat(x)?
..., I find Number to be more reasonable, so I almost always use Number personally (and you'll find that a lot of the internal JavaScript functions use Number as well). If someone types '1x' I prefer to show an error rather than treat it as if they had typed '1'. The only time I really make an exceptio...
Building vs. Compiling (Java)
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The "Build" is a process that covers all the steps required to create a "deliverable" of your software. In the Java world, this typically includes:
Generating sources (sometimes).
Compiling sources.
Compiling test sources.
Executing tests (unit tests, integrat...
How to limit the amount of concurrent async I/O operations?
... Stephen Toub, but the less announced news is that the async semaphore actually made it into the Beta release of .NET 4.5
If you look at our beloved SemaphoreSlim class (which you should be using since it's more performant than the original Semaphore), it now boasts the WaitAsync(...) series of ove...