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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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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...
How to shuffle a std::vector?
...but I think it's not very efficient because it needs an intermediate array and it needs to know the item type (DeckCard in this example):
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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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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>...
Find out time it took for a python script to complete execution
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Do you execute the script from the command line on Linux or UNIX? In that case, you could just use
time ./script.py
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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...
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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Is there a way to instantiate objects from a string holding their class name?
...<DerivedA>;
map["DerivedB"] = &createInstance<DerivedB>;
And then you can do
return map[some_string]();
Getting a new instance. Another idea is to have the types register themself:
// in base.hpp:
template<typename T> Base * createT() { return new T; }
struct BaseFactor...
Reimport a module in python while interactive
... useful if you have edited the module source file using an external editor and want to try out the new version without leaving the Python interpreter.
If running Python 3.4 and up, do import importlib, then do importlib.reload(nameOfModule).
Don't forget the caveats of using this method:
When ...