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What is the difference between “ is None ” and “ ==None ”
...ison any way it chooses, and it
can choose to make comparison against
None mean something (which actually
makes sense; if someone told you to
implement the None object from
scratch, how else would you get it to
compare True against itself?).
Practically-speaking, there is not much diff...
How to move an element into another element?
I would like to move one DIV element inside another. For example, I want to move this (including all children):
15 Answers
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Difference between getContext() , getApplicationContext() , getBaseContext() and “this”
...ess resources (e.g. openFileInput(), getString()), interact with other components (e.g. sendBroadcast(), registerReceiver()), requests permissions (e.g. checkCallingOrSelfPermission()) and resolving file system locations (e.g. getFilesDir()). ContextWrapper is really useful to work around device/ver...
C++ Singleton design pattern
...zy-evaluated, guaranteed-destruction, not-technically-thread-safe:
Can any one provide me a sample of Singleton in c++?
Here is an updated C++11 implementation of the Singleton design pattern that is lazy-evaluated, correctly-destroyed, and thread-safe.
class S
{
public:
static S&...
How to ignore the first line of data when processing CSV data?
...me it's the prescribed way to do it. I agree that doing it on the basis of one line of data doesn't seem like it would always be enough data to make such a determination—but I have no idea since how the Sniffer works isn't described. FWIW I've never seen has_header(file.readline()) being used and ...
Python Flask, how to set content type
...n I did it, I ended up with two Content-Type headers in response - default one and added one.
– omikron
Feb 2 '17 at 16:15
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Git fast forward VS no fast forward merge
...you still want sometimes to have each commit in the mainline correspond to one feature. So you treat a feature branch with a bunch of commits as a single unit, and merge them as a single unit. It is clear from your history when you do feature branch merging with --no-ff.
If you do not care about su...
How do you delete all text above a certain line
...top of the file.
Also
dG
will delete all lines at or below the current one
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What is the purpose of Rank2Types?
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To add some words connecting my answer to this one: consider the Haskell function f' g x y = g x + g y. Its inferred rank-1 type is forall a r. Num r => (a -> r) -> a -> a -> r. Since forall a is outside the function arrows, the caller must first pick a typ...
Can I have multiple background images using CSS?
...it possible to have two background images? For instance, I'd like to have one image repeat across the top (repeat-x), and another repeat across the entire page (repeat), where the one across the entire page is behind the one which repeats across the top.
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