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Where and why do I have to put the “template” and “typename” keywords?
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(See here also for my C++11 answer)
In order to parse a C++ program, the compiler needs to know whether certain names are types or not. The following example demonstrates that:
t * f;
How should this be parsed? For many languages a compi...
Check empty string in Swift?
In Objective C, one could do the following to check for strings:
14 Answers
14
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Django filter versus get for single object?
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get() is provided specifically for this case. Use it.
Option 2 is almost precisely how the get() method is actually implemented in Django, so there should be no "performance" difference (and the fact that you're thinking about it indicates you're violating...
Should functions return null or an empty object?
...actice when returning data from functions. Is it better to return a Null or an empty object? And why should one do one over the other?
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My Understanding of HTTP Polling, Long Polling, HTTP Streaming and WebSockets
I have read many posts on SO and the web regarding the keywords in my question title and learned a lot from them. Some of the questions I read are related to specific implementation challenges while others focus on general concepts. I just want to make sure I understood all of the concepts and the r...
What is Data Transfer Object?
...pplications. They also make great models in the MVC pattern.
Another use for DTOs can be to encapsulate parameters for method calls. This can be useful if a method takes more than 4 or 5 parameters.
When using the DTO pattern, you would also make use of DTO assemblers. The assemblers are used to c...
Rolling or sliding window iterator?
... need a rolling window (aka sliding window) iterable over a sequence/iterator/generator. Default Python iteration can be considered a special case, where the window length is 1. I'm currently using the following code. Does anyone have a more Pythonic, less verbose, or more efficient method for do...
Copying PostgreSQL database to another server
... localhost -U localuser dbname | psql -h remotehost -U remoteuser dbname
or
pg_dump -C -h remotehost -U remoteuser dbname | psql -h localhost -U localuser dbname
using psql or pg_dump to connect to a remote host.
With a big database or a slow connection, dumping a file and transfering the file...
What exactly are iterator, iterable, and iteration?
What is the most basic definition of "iterable", "iterator" and "iteration" in Python?
13 Answers
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What is the correct way to represent null XML elements?
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xsi:nil is the correct way to represent a value such that:
When the DOM Level 2 call getElementValue() is issued, the NULL value is returned.
xsi:nil is also used to indicate a valid element with no content even if that elements content type...