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The differences between .build, .create, and .create! and when should they be used?
So I've been seeing people using .build , .create , and .create! within their controllers more and more lately. What's the difference from just using .new and passing the param'd object and then .save ? Are there pros and cons? Does using these other methods offer benefits?
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Does the APNS device token ever change, once created?
...st ensures that only APNs generates
the token which it will later honor, and it can assure itself that a
token handed to it by a device is the same token that it previously
provisioned for that particular device—and only for that device.
If the user restores backup data to a new device ...
Best practices for overriding isEqual: and hash
...ive you do
result = prime * result + var
For objects you use 0 for nil and otherwise their hashcode.
result = prime * result + [var hash];
For booleans you use two different values
result = prime * result + ((var)?1231:1237);
Explanation and Attribution
This is not tcurdt's work, and ...
What do the following phrases mean in C++: zero-, default- and value-initialization?
...thing to realize is that 'value-initialization' is new with the C++ 2003 standard - it doesn't exist in the original 1998 standard (I think it might be the only difference that's more than a clarification). See Kirill V. Lyadvinsky's answer for the definitions straight from the standard.
See this ...
Hidden Features of Xcode
...h a huge influx of newbies to Xcode, I'm sure there are lots of Xcode tips and tricks to be shared.
89 Answers
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How to clear gradle cache?
I'm trying to use Android Studio, and the first time I boot it up, it takes like 45 MINUTES to compile... If I don't quit the application, it is okay - each subsequent compilation/running the app will take around 45 seconds.
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Cross compile Go on OSX?
I am trying to cross-compile a go app on OSX to build binaries for windows and linux. I have read everything what I could find on the net. Closest example that I have found has been published on (apart from many unfinished discussions on go-nuts mailing list):
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Should each and every table have a primary key?
I'm creating a database table and I don't have a logical primary key assigned to it. So, I'm thinking about leaving it without a primary key, but I'm feeling a bit guilty about it. Should I?
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Open a URL in a new tab (and not a new window)
... demonstrate this.)
CSS3 proposed target-new, but the specification was abandoned.
The reverse is not true; by specifying dimensions for the window in the third argument of window.open(), you can trigger a new window when the preference is for tabs.
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grid controls for ASP.NET MVC? [closed]
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We have been using jqGrid on a project and have had some good luck with it. Lots of options for inline editing, etc. If that stuff isn't necessary, then we've just used a plain foreach loop like @Hrvoje.
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