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Should I prefer pointers or references in member data?

... be null. This can be an advantage, but if the code ever needs changing to allow rebinding or for the member to be null, all uses of the member need to change unlike pointer members, references can't easily be replaced by smart pointers or iterators as refactoring might require Whenever a reference ...
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Does static constexpr variable inside a function make sense?

...n with static const integers.) The C++ object model (§1.9) requires that all objects other than bit-fields occupy at least one byte of memory and have addresses; furthermore all such objects observable in a program at a given moment must have distinct addresses (paragraph 6). This does not quite r...
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Is there any performance gain in indexing a boolean field?

...udes a WHERE isok=1 . As the name implies, isok is a boolean field (actually a TINYINT(1) UNSIGNED that is set to 0 or 1 as needed). ...
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Libraries do not get added to APK anymore after upgrade to ADT 22

...d wrong to have every Developer [that uses Eclipse and Libraries] go in to all of their library projects and mark "Android Private Libraries" as Exported? This makes me think that we have all mistaken the intention of Google adding this new "feature" in the first place. Maybe we aren't supposed to m...
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Runnable with a parameter?

...ble that accepts a parameter" although I know that such runnable doesn't really exist. 7 Answers ...
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LINQPad [extension] methods [closed]

...ed queries / samples (for an example, execute a search using Edit | Search All) Highlight - wraps an object so that it will highlight in yellow when Dumped HorizontalRun - lets you Dump a series of objects on the same line LINQPad also provides the HyperLinq class. This has two purposes: the first...
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Speed up the loop operation in R

...Biggest problem and root of ineffectiveness is indexing data.frame, I mean all this lines where you use temp[,]. Try to avoid this as much as possible. I took your function, change indexing and here version_A dayloop2_A <- function(temp){ res <- numeric(nrow(temp)) for (i in 1:nrow(te...
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How to convert int to QString?

... Then you probably want to work on pre-allocated buffers... but this sounds like a separate question. – Georg Fritzsche Apr 6 '17 at 4:45 a...
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Does name length impact performance in Redis?

I like to use verbose names in Redis, for instance set-allBooksBelongToUser:$userId . 4 Answers ...
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Stretch and scale CSS background

... background-size: cover; } cover means stretching the image either vertically or horizontally so it never tiles/repeats. That would work for Safari 3 (or later), Chrome, Opera 10+, Firefox 3.6+, and Internet Explorer 9 (or later). For it to work with lower verions of Internet Explorer, try th...