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django - why is the request.POST object immutable?
...nts a full set of mutation methods including __setitem__, __delitem__, pop and clear. It implements immutability by checking a flag when you call one of the mutation methods. And when you call the copy method you get another QueryDict instance with the mutable flag turned on.
For performance improve...
Python: avoid new line with print command [duplicate]
I've started programming today and have this issue with Python. It's pretty dumb but I can't figure out how to do it. When I use the print command, it prints whatever I want and then goes to a different line. For example:
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How to replace spaces in file names using a bash script
...end a safe solution to recursively replace spaces with underscores in file and directory names starting from a given root directory? For example:
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Can comments be used in JSON?
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No.
The JSON should all be data, and if you include a comment, then it will be data too.
You could have a designated data element called "_comment" (or something) that would be ignored by apps that use the JSON data.
You would probably be better having the...
What's the $unwind operator in MongoDB?
...om your mind. The way that it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what...
Fastest way to get the first object from a queryset in django?
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Use the convenience methods .first() and .last():
MyModel.objects.filter(blah=blah).first()
They both swallow the resulting exception and return None if the queryset returns no objects.
These were added in Django 1.6, which was released in Nov 2013.
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Why use String.Format? [duplicate]
Why would anyone use String.Format in C# and VB .NET as opposed to the concatenation operators ( & in VB, and + in C#)?
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How to throw std::exceptions with variable messages?
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what's the difference between this and an std::stringstream? It appears to contain a stringstream, but has (as far as I can tell), no extra functionality.
– matts1
Sep 4 '16 at 1:43
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What are “connecting characters” in Java identifiers?
I am reading for SCJP and I have a question regarding this line:
7 Answers
7
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Performance of Find() vs. FirstOrDefault() [duplicate]
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I was able to mimic your results so I decompiled your program and there is a difference between Find and FirstOrDefault.
First off here is the decompiled program. I made your data object an anonmyous data item just for compilation
List<\u003C\u003Ef__AnonymousType0<string>...