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When should I use nil and NULL in Objective-C?
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technically, they are exactly equal, you can send messages to both nil and to NULL. Idiomatically though nil is usually used to represent an object
– cobbal
Oct 14 '09 at 5:43
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Python multiprocessing PicklingError: Can't pickle
...the one you posted:
Exception in thread Thread-2:
Traceback (most recent call last):
File "/usr/lib/python2.7/threading.py", line 552, in __bootstrap_inner
self.run()
File "/usr/lib/python2.7/threading.py", line 505, in run
self.__target(*self.__args, **self.__kwargs)
File "/usr/lib/p...
How do you build a Singleton in Dart?
... There's the weird syntax Singleton._internal(); that looks like a method call when it's really a constructor definition. There's the _internal name. And there's the nifty language design point that Dart lets you start out (dart out?) using an ordinary constructor and then, if needed, change it to a...
How to simulate target=“_blank” in JavaScript
...cking window.open is kinda the point of pop-up blockers! If you make the call in response to a click action it has a better chance of not being blocked.
– William Denniss
Aug 18 '11 at 15:16
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python: how to identify if a variable is an array or a scalar
I have a function that takes the argument NBins . I want to make a call to this function with a scalar 50 or an array [0, 10, 20, 30] . How can I identify within the function, what the length of NBins is? or said differently, if it is a scalar or a vector?
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What is the volatile keyword useful for?
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volatile has semantics for memory visibility. Basically, the value of a volatile field becomes visible to all readers (other threads in particular) after a write operation completes on it. Without volatile, readers could see some non-updated value.
To answer your question: Y...
Casting vs using the 'as' keyword in the CLR
...d within the if body.) That's slightly annoying in some cases, so if you really care about introducing the smallest number of variables possible in every scope, you might still want to use is followed by a cast.
I don't think any of the answers so far (at the time of starting this answer!) have r...
python NameError: global name '__file__' is not defined
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I had the same problem with PyInstaller and Py2exe so I came across the resolution on the FAQ from cx-freeze.
When using your script from the console or as an application, the functions hereunder will deliver you the "execution path", not the "actual file pa...
How to update PATH variable permanently from Windows command line?
... do this can be found on MSDN. The key extract is this:
To programmatically add or modify system environment variables, add them to the HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager\Environment registry key, then broadcast a WM_SETTINGCHANGE message with lParam set to the s...
Where and how is the _ViewStart.cshtml layout file linked?
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Starting with the ASP.NET MVC 3 Beta release, you can now add a file
called _ViewStart.cshtml (or _ViewStart.vbhtml for VB) underneath the
\Views folder of your project:
The _ViewStart file can be used to define common view code that you
want to execute at the start of each View’s re...