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How to make an immutable object in Python?
...butes can be accessed via [0] etc., but at least it's considerably shorter and provides the additional advantage of being compatible with pickle and copy.
namedtuple creates a type similar to what I described in this answer, i.e. derived from tuple and using __slots__. It is available in Python 2....
When is the init() function run?
....")
}
}
AnswerToLife() is guaranteed to run before init() is called, and init() is guaranteed to run before main() is called.
Keep in mind that init() is always called, regardless if there's main or not, so if you import a package that has an init function, it will be executed.
Additionally,...
How to use Class in Java?
There's a good discussion of Generics and what they really do behind the scenes over at this question , so we all know that Vector<int[]> is a vector of integer arrays, and HashTable<String, Person> is a table of whose keys are strings and values Person s.
However, what stumps me ...
C# - Selectively suppress custom Obsolete warnings
...on - introduce a new build configuration that doesn't have them as errors, and only run the unit tests there. Or (ugly) use reflection...
– Jon Skeet
Aug 14 '19 at 10:30
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Android Studio needs JDK 7 for Android-L mac
I was trying to look how my app looks in material design and I would like to use the new cards lib.
My Problem is, that it's giving me this error within my gradle file and I need to fix that.
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How can I reliably determine the type of a variable that is declared using var at design time?
... to quickly build up a database of information about what namespace, types and methods (and constructors, etc) are in the source code of the program. Analyzing every single line of code in every method body would take way too long if you're trying to do it between keystrokes.
When the IDE needs to...
Why are mutable structs “evil”?
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So if you change a copy you are changing only that copy, not the original and not any other copies which might be around.
If your struct is immutable then all automatic copies resulting from being passed by value will be the same.
If you want to change it you have to consciously do it by creating...
C# Lambda expressions: Why should I use them?
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Lambda expressions are a simpler syntax for anonymous delegates and can be used everywhere an anonymous delegate can be used. However, the opposite is not true; lambda expressions can be converted to expression trees which allows for a lot of the magic like LINQ to SQL.
The following ...
Is there a way to iterate over a dictionary?
...d a key in order to get a value . But how can I iterate over all keys and values in a NSDictionary , so that I know what keys there are, and what values there are? I know there is something called a for-in-loop in JavaScript . Is there something similar in Objective-C ?
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How to tell if rails is in production?
...ed script/server -e production to start rails in production mode. It did and I got no errors. However how do I tell if it is in production mode? I tried a non-existent route, and I got a similar error page I did in development.
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