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Django - how to create a file and save it to a model's FileField?
Here's my model. What I want to do is generate a new file and overwrite the existing one whenever a model instance is saved:
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Understanding promises in Node.js
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Promises in node.js promised to do some work and then had separate callbacks that would be executed for success and failure as well as handling timeouts. Another way to think of promises in node.js was that they were emitters that could emit only two events: success and...
How can I get the console logs from the iOS Simulator?
...ut, so you can see the logs mixed up with system logs.
Open the Terminal and type: tail -f /var/log/system.log
Then run the simulator.
EDIT:
This stopped working on Mavericks/Xcode 5. Now you can access the simulator logs in its own folder: ~/Library/Logs/iOS Simulator/<sim-version>/syste...
What is your most productive shortcut with Vim?
I've heard a lot about Vim , both pros and cons.
It really seems you should be (as a developer) faster with Vim than with any other editor.
I'm using Vim to do some basic stuff and I'm at best 10 times less productive with Vim.
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What is stack unwinding?
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Stack unwinding is usually talked about in connection with exception handling. Here's an example:
void func( int x )
{
char* pleak = new char[1024]; // might be lost => memory leak
std::string s( "hello world" ); // will be properly destructed
if ( x ) throw std::runtime_error(...
Xcode duplicate/delete line
Coming from Eclipse and having been used to duplicate lines all the time, it's pretty strange finding out that Xcode has no such function. Or does it?
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linq where list contains any in list
...ains method for these kind of queries. I was curious by seeing your answer and checked the internal implementation and found that Intersect uses Set. Can you tell me the performance difference between those two methods?
– rebornx
Feb 17 '17 at 9:02
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LINQ Ring: Any() vs Contains() for Huge Collections
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Contains() is an instance method, and its performance depends largely on the collection itself. For instance, Contains() on a List is O(n), while Contains() on a HashSet is O(1).
Any() is an extension method, and will simply go through the collection, applyi...
string.IsNullOrEmpty(string) vs. string.IsNullOrWhiteSpace(string)
...bad practice when there is string.IsNullOrWhiteSpace(string) in .NET 4.0 and above?
9 Answers
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Is it pythonic to import inside functions?
... new code to an existing file I'll usually do the import where it's needed and then if the code stays I'll make things more permanent by moving the import line to the top of the file.
One other point, I prefer to get an ImportError exception before any code is run -- as a sanity check, so that's an...