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When to use IMG vs. CSS background-image?

...ze. Use IMG for multiple overlay images in IE6. Use IMG with a z-index in order to stretch a background image to fill its entire window.Note, this is no longer true with CSS3 background-size; see #6 below. Using img instead of background-image can dramatically improve performance of animations ove...
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What is the difference between a 'closure' and a 'lambda'?

... ) OK, now it's time to solve the other mystery: what is a closure. In order to do that, let's talk about symbols (variables) in lambda expressions. As I said, what the lambda abstraction does is binding a symbol in its subexpression, so that it becomes a substitutible parameter. Such a symbol ...
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How do C++ class members get initialized if I don't do it explicitly?

... mem-initializer-list, and members can only be initialized in a prescribed order (basically the order in which the members are declared in the class). Thus, the members of Example can only be initialized in the order: ptr, name, pname, rname, crname, and age. When you do not specify a mem-initializ...
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Who architected / designed C++'s IOStreams, and would it still be considered well-designed by today'

...ontext for the translators. If your string formatting routine supports re-ordering (like the POSIX $ printf parameters), then it also better handles differences in word order between languages. share | ...
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View's getWidth() and getHeight() returns 0

..., etc. as stated by Romain Guy: The UI event queue will process events in order. After setContentView() is invoked, the event queue will contain a message asking for a relayout, so anything you post to the queue will happen after the layout pass Example: final View view=//smth; ... view.post(new R...
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Good or bad practice for Dialogs in wpf with MVVM?

...del that exposes things such as the title, the standad buttons to show (in order to have a consistent apparence across all dialogs), a RequestClose event, and a few other things to be able to control the window size and behavior ...
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How to add a delay for a 2 or 3 seconds [closed]

.... As for my case, I need to sleep the thread for 0.6 seconds precisely in order to avoid an index constrain when inserting into the database. – GunWanderer Apr 19 '18 at 16:48 ...
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Replacing NAs with latest non-NA value

... = TRUE), y = sample(c(1:4, rep(NA, 4)), 20 , replace = TRUE)) dt <- dt[order(group)] dt[, y_forward_fill := y[1], .(group, cumsum(!is.na(y)))] dt group y y_forward_fill 1: a NA NA 2: a NA NA 3: a NA NA 4: a 2 2 5: a ...
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How do I add more members to my ENUM-type column in MySQL?

...o the end is fine, since you just add meaning old values. but changing the order / removing enums will make those numbers undefined. (eg. 1=>italy, 2=>germany), then extending will be (1=>italy, 2=>germany, 3=>sweenden). – lintabá Mar 21 '19 at ...
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PostgreSQL error: Fatal: role “username” does not exist

... system user to have initialized the database cluster. The manual: In order to bootstrap the database system, a freshly initialized system always contains one predefined role. This role is always a “superuser”, and by default (unless altered when running initdb) it will have the same ...