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Return None if Dictionary key is not available
I need a way to get a dictionary value if its key exists, or simply return None , if it does not.
11 Answers
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PreparedStatement IN clause alternatives?
...ng a SQL IN clause with instances of java.sql.PreparedStatement , which is not supported for multiple values due to SQL injection attack security issues: One ? placeholder represents one value, rather than a list of values.
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C++, What does the colon after a constructor mean? [duplicate]
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As others have said, it's an initialisation list. You can use it for two things:
Calling base class constructors
Initialising member variables before the body of the constructor executes.
For case #1, I assume you understand inheritance (if that's not the c...
Implementing Comments and Likes in database
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The most extensible solution is to have just one "base" table (connected to "likes", tags and comments), and "inherit" all other tables from it. Adding a new kind of entity involves just adding a new "inherited" table - it then automatically plugs into t...
How to escape special characters in building a JSON string?
Here is my string
11 Answers
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Python loop that also accesses previous and next values
How can I iterate over a list of objects, accessing the previous, current, and next items? Like this C/C++ code, in Python?
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When should I use C++ private inheritance?
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Note after answer acceptance: This is NOT a complete answer. Read other answers like here (conceptually) and here (both theoretic and practic) if you are interested in the question. This is just a fancy trick that can be achieved with private inheritance. W...
Difference between class and type
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A class is a type. An interface is a type. A primitive is a type. An array is a type.
Therefore, every type is also either a class (including an enum constant), an interface, a primitive, or an array.
There are two distinct categ...
What is the difference/usage of homebrew, macports or other package installation tools? [closed]
I've just recently switched to a Mac from Ubuntu. I was disappointed that mac doesn't have the convenient sudo apt-get in Ubuntu. I've heard that I should use homebrew but I'm not exactly sure what homebrew or macports does?
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What is the purpose of the “final” keyword in C++11 for functions?
What is the purpose of the final keyword in C++11 for functions? I understand it prevents function overriding by derived classes, but if this is the case, then isn't it enough to declare as non-virtual your final functions? Is there another thing I'm missing here?
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