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What does the property “Nonatomic” mean?

...nge/read the property at once, badness can happen. You can get partially-written values or over-released/retained objects, which can easily lead to crashes. (This is potentially a lot faster than an atomic accessor, though.) If you use the default (which is atomic; there used to be no keyword for t...
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What's the point of having pointers in Go?

...that pointers in Go allow mutation of a function's arguments, but wouldn't it have been simpler if they adopted just references (with appropriate const or mutable qualifiers). Now we have pointers and for some built-in types like maps and channels implicit pass by reference. ...
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mongoDB/mongoose: unique if not null

...the desired behavior of ensuring unique values but allowing multiple docs without the field by setting the sparse option to true when defining the index. As in: email : {type: String, trim: true, index: true, unique: true, sparse: true} Or in the shell: db.users.ensureIndex({email: 1}, {unique:...
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How do I find the .NET version?

...follow | edited Apr 23 '17 at 11:25 Peter Mortensen 26.5k2121 gold badges9292 silver badges122122 bronze badges ...
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In Objective-C, how do I test the object type?

... If your object is myObject, and you want to test to see if it is an NSString, the code would be: [myObject isKindOfClass:[NSString class]] Likewise, if you wanted to test myObject for a UIImageView: [myObject isKindOfClass:[UIImageView class]] ...
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How to round up a number to nearest 10?

...ivide by 10, do the ceil, then multiply by 10 to reduce the significant digits. $number = ceil($input / 10) * 10; Edit: I've been doing it this way for so long.. but TallGreenTree's answer is cleaner. share | ...
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Use CSS3 transitions with gradient backgrounds

I'm trying to transition on hover with css over a thumbnail so that on hover, the background gradient fades in. The transition isn't working, but if I simply change it to an rgba() value, it works fine. Are gradients not supported? I tried using an image too, it won't transition the image either. ...
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In Laravel, the best way to pass different types of flash messages in the session

...es. As far as I'm aware in my controller action I can set a flash message either by going 15 Answers ...
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Best way to remove an event handler in jQuery?

...meone enters a number into the text box that this input-image is paired with, I setup an event handler for the input-image . Then when the user clicks the image , they get a little popup to add some notes to the data. ...
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Determine font color based on background color

Given a system (a website for instance) that lets a user customize the background color for some section but not the font color (to keep number of options to a minimum), is there a way to programmatically determine if a "light" or "dark" font color is necessary? ...