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Objective-C ARC: strong vs retain and weak vs assign
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@Pascal: weak references aren't allowed in deployment targets where the os is not 5.0 or higher. So for older projects you can still use assign, but if you move to newer versions you have to switch to weak
– Mattia
Feb...
When to use enumerateObjectsUsingBlock vs. for
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Ultimately, use whichever pattern you want to 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 fas...
Measure time in Linux - time vs clock vs getrusage vs clock_gettime vs gettimeofday vs timespec_get?
...at time is measured by the clock? (real, user, system, or, hopefully not, wall-clock?)
What is the precision of the clock? (s, ms, µs, or faster?)
After how much time does the clock wrap around? Or is there some mechanism to avoid this?
Is the clock monotonic, or will it change with changes in the ...
What does “for” attribute do in HTML tag?
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The <label> tag allows you to click on the label, and it will be treated like clicking on the associated input element. There are two ways to create this association:
One way is to wrap the label element around the input element:
<label...
overlay two images in android to set an imageview
...XML then simply set the image, or you can configure a LayerDrawable dynamically in code.
Solution #1 (via XML):
Create a new Drawable XML file, let's call it layer.xml:
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
<item android:drawable="@drawable/t" />
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Intro to GPU programming [closed]
Everyone has this huge massively parallelized supercomputer on their desktop in the form of a graphics card GPU.
9 Answers
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PowerShell script to return versions of .NET Framework on a machine?
...t). It also outputs both Client and Full on 4.0 (if you have them both installed):
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based o...
Adding git branch on the Bash command prompt
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git 1.9.3 or later: use __git_ps1
Git provides a shell script called git-prompt.sh, which includes a function __git_ps1 that
prints text to add to bash PS1 prompt (includes branch name)
Its most basic usage is:
$ __git_ps1
(master)
It also takes an optional format string:
$ __g...
How do you round a floating point number in Perl?
.... For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implements
ceil(), floor(), and a number of other mathematical and trigonometric
func...
How do I delete all messages from a single queue using the CLI?
How do I delete all messages from a single queue using the cli?
I have the queue name and I want to clean it.
9 Answers
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