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How do I implement an Objective-C singleton that is compatible with ARC?
...n;
dispatch_once(&onceToken, ^{
sharedInstance = [[MyClass alloc] init];
// Do any other initialisation stuff here
});
return sharedInstance;
}
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How can I display an image from a file in Jupyter Notebook?
...y? (Don't tell me that otherwise it doesn't work. Please explain why this call to 'display' is needed in a loop but not if you just dispaly one image).
– Kris
May 1 '17 at 1:25
12
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What Vim command(s) can be used to quote/unquote words?
...tes.
Change single quotes to double quotes
va':s/\%V'\%V/"/g
va' - Visually select the quoted word and the quotes.
:s/ - Start a replacement.
\%V'\%V - Only match single quotes that are within the visually selected region.
/"/g - Replace them all with double quotes.
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Can table columns with a Foreign Key be NULL?
...d Mar 2 '10 at 21:37
Daniel VassalloDaniel Vassallo
301k6666 gold badges475475 silver badges424424 bronze badges
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Is there a way to get the source code from an APK file?
The hard drive on my laptop just crashed and I lost all the source code for an app that I have been working on for the past two months.
All I have is the APK file that is stored in my email from when I sent it to a friend.
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How do I install from a local cache with pip?
I install a lot of the same packages in different virtualenv environments. Is there a way that I can download a package once and then have pip install from a local cache?
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How do you copy and paste into Git Bash
...Edit -> Paste which is exactly what I want! No more typing API code manually!
– Trav L
Feb 21 '10 at 1:08
27
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PHP: How to remove all non printable characters in a string?
...to remove other chars...
If you're dealing with Unicode, there are potentially many non-printing elements, but let's consider a simple one: NO-BREAK SPACE (U+00A0)
In a UTF-8 string, this would be encoded as 0xC2A0. You could look for and remove that specific sequence, but with the /u modifier in ...
brew install mysql on macOS
I'm trying to setup up MySQL on mac os 10.6 using Homebrew by brew install mysql 5.1.52 .
16 Answers
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How do I create a basic UIButton programmatically?
...height: 500)
myButton.addTarget(self, action: #selector(pressedAction(_:)), for: .touchUpInside)
self.view.addSubview( myButton)
func pressedAction(_ sender: UIButton) {
// do your stuff here
print("you clicked on button \(sender.tag)")
}
SwiftUI
for example you get the step by ...