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What is the difference between “ is None ” and “ ==None ”
...
class Foo:
def __eq__(self,other):
return True
foo=Foo()
print(foo==None)
# True
print(foo is None)
# False
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How to catch curl errors in PHP
...
You can use the curl_error() function to detect if there was some error. For example:
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $your_url);
curl_setopt($ch, CURLOPT_FAILONERROR, true); // Required for HTTP error codes to be reported via ...
Why is a ConcurrentModificationException thrown and how to debug it
...his will throw a ConcurrentModificationException when the it.hasNext() is called the second time.
The correct approach would be
Iterator it = map.entrySet().iterator();
while (it.hasNext())
{
Entry item = it.next();
it.remove();
}
Assuming this iterator supports the remo...
Advantages of std::for_each over for loop
...
The nice thing with C++11 (previously called C++0x), is that this tiresome debate will be settled.
I mean, no one in their right mind, who wants to iterate over a whole collection, will still use this
for(auto it = collection.begin(); it != collection.end() ; ++...
How to change context root of a dynamic web project in Eclipse?
...hought I'd answer anyway.
Some of these answers give workarounds. What actually must happen is that you clean and re-publish your project to "activate" the new URI. This is done by right-clicking your server (in the Servers view) and choosing Clean. Then you start (or restart it). Most of the other ...
Is std::unique_ptr required to know the full definition of T?
...s. However shared_ptr and unique_ptr are partial exceptions. Some, but not all of their members can be instantiated with incomplete types. The motivation for this is to support idioms such as pimpl using smart pointers, and without risking undefined behavior.
Undefined behavior can occur when you h...
Objective-C: difference between id and void *
... will cause premature reaping of objects if _superPrivateDoNotTouch is actually an object. Don't do that.
attempting to invoke a method on a reference of void * type will barf up a compiler warning.
attempting to invoke a method on an id type will only warn if the method being called has not been d...
Collect successive pairs from a stream
...eamEx library which extends standard streams provides a pairMap method for all stream types. For primitive streams it does not change the stream type, but can be used to make some calculations. Most common usage is to calculate differences:
int[] pairwiseDiffs = IntStreamEx.of(input).pairMap((a, b)...
View contents of database file in Android Studio
...w these steps (for actual device, scroll to the bottom):
Download and install SQLiteBrowser.
Copy the database from the device to your PC:
Android Studio versions < 3.0:
Open DDMS via Tools > Android > Android Device Monitor
Click on your device on the left.
You should see your applica...
Quick and easy file dialog in Python?
...a UI, but right now I'm prompting the user for the file to parse using raw_input which is most unfriendly, especially because the user can't copy/paste the path. I would like a quick and easy way to present a file selection dialog to the user, they can select the file, and then it's loaded to the...