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What is an “unwrapped value” in Swift?
...
cantBeNil = nil // can't do this
To get the value from your variable if it is optional, you have to unwrap it. This just means putting an exclamation point at the end.
var canBeNil : Int? = 4
println(canBeNil!)
Your code should look like this:
let optionalSquare: Square? = Square(sideLength: ...
Capturing standard out and error with Start-Process
...That's how Start-Process was designed for some reason. Here's a way to get it without sending to file:
$pinfo = New-Object System.Diagnostics.ProcessStartInfo
$pinfo.FileName = "ping.exe"
$pinfo.RedirectStandardError = $true
$pinfo.RedirectStandardOutput = $true
$pinfo.UseShellExecute = $false
$pin...
How can I resize an image using Java?
...edBI.createGraphics();
if (preserveAlpha) {
g.setComposite(AlphaComposite.Src);
}
g.drawImage(originalImage, 0, 0, scaledWidth, scaledHeight, null);
g.dispose();
return scaledBI;
}
...
Is it possible to run JavaFX applications on iOS, Android or Windows Phone 8?
Can one develop an entire application using JavaFX and run it on iOS, Android or Windows Phone 8, without writing platform-specific code?
...
How expensive is RTTI?
I understand that there is a resource hit from using RTTI, but how big is it? Everywhere I've looked just says that "RTTI is expensive," but none of them actually give any benchmarks or quantitative data reguarding memory, processor time, or speed.
...
How do you set, clear, and toggle a single bit?
How do you set, clear, and toggle a bit?
30 Answers
30
...
Difference between string and char[] types in C++
I know a little C and now I'm taking a look at C++.
I'm used to char arrays for dealing with C strings, but while I look at C++ code I see there are examples using both string type and char arrays:
...
Why doesn't Java Map extend Collection?
...t
mappings are not collections and
collections are not mappings. Thus, it
makes little sense for Map to extend
the Collection interface (or vice
versa).
If a Map is a Collection, what are the
elements? The only reasonable answer
is "Key-value pairs", but this
provides a very lim...
When to use enumerateObjectsUsingBlock vs. for
...o use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fast or faster than fast enumeration (for(... in ......
CABasicAnimation resets to initial value after animation completes
I am rotating a CALayer and trying to stop it at its final position after animation is completed.
15 Answers
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