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Double negation (!!) in javascript - what is the purpose? [duplicate]
...ue
null to true
+0 to true
-0 to true
'' to true
NaN to true
false to true
All other expressions to false
Then the other ! negates it again. A concise cast to boolean, exactly equivalent to ToBoolean simply because ! is defined as its negation. It’s unnecessary here, though, because it’s only ...
Best way to center a on a page vertically and horizontally? [duplicate]
Best way to center a <div> element on a page both vertically and horizontally?
30 Answers
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CSS background opacity with rgba not working in IE 8
...tydot), and which matches the transparency of your background.
EDIT : to fall back for IE6+ support, you can specify bkgd chunk for the png, this is a color which will replace the true alpha transparency if it is not supported. You can fix it with gimp eg.
...
'Best' practice for restful POST response
... to get the ID easily and to get the timestamps when relevant.
This is actually the default behavior got when scaffolding with Rails.
I really do not see any advantage to returning only the ID and doing a GET request after, to get the data you could have got with your initial POST.
Anyway as long ...
Android Studio Editor Font Sizing
...
They didn't make this very obvious, did they?
All you have to do is click the "Save As" button to create a new profile. You can't change the font because you can't overwrite the default profiles.
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Django using get_user_model vs settings.AUTH_USER_MODEL
...s.AUTH_USER_MODEL will delay the retrieval of the actual model class until all apps are loaded. get_user_model will attempt to retrieve the model class at the moment your app is imported the first time.
get_user_model cannot guarantee that the User model is already loaded into the app cache. It mi...
Get the position of a div/span tag
...n will tell you the x,y position of the element relative to the page. Basically you have to loop up through all the element's parents and add their offsets together.
function getPos(el) {
// yay readability
for (var lx=0, ly=0;
el != null;
lx += el.offsetLeft, ly += el.off...
How to skip over an element in .map()?
...nce it has some cost, you can use the more general .reduce(). You can generally express .map() in terms of .reduce:
someArray.map(function(element) {
return transform(element);
});
can be written as
someArray.reduce(function(result, element) {
result.push(transform(element));
return result;
}...
Keep only date part when using pandas.to_datetime
...fault represents the dates with datetime64[ns] even though the dates are all daily only.
I wonder whether there is an elegant/clever way to convert the dates to datetime.date or datetime64[D] so that, when I write the data to CSV, the dates are not appended with 00:00:00 . I know I can conver...
How can a Java program get its own process ID?
...There exists no platform-independent way that can be guaranteed to work in all jvm implementations.
ManagementFactory.getRuntimeMXBean().getName() looks like the best (closest) solution, and typically includes the PID. It's short, and probably works in every implementation in wide use.
On linux+wind...