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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...
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 ...
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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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...
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...
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 ...
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
...
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 ...
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
...
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 ...
