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Difference between Inheritance and Composition
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They are absolutely different. Inheritance is an "is-a" relationship. Composition is a "has-a".
You do composition by having an instance of another class C as a field of your class, instead of extending C. A good example where composi...
How do I use a custom deleter with a std::unique_ptr member?
I have a class with a unique_ptr member.
6 Answers
6
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How to re import an updated package while in Python Interpreter? [duplicate]
...ython Interpreter, and when I see an error, I quickly update the .py file. But how do I make it reflect on the Interpreter ? So, far I have been exiting and reentering the Interpreter because re importing the file again is not working for me.
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Why does ++[[]][+[]]+[+[]] return the string “10”?
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In JavaScript, it is true that +[] === 0. + converts something into a number, and in this case it will come down to +"" or 0 (see specification details below).
Therefore, we can simplify it (++ has precendence over +):
++[[]][0]
+
[0]
Because [[]][0] means: get the first element from [[]], it ...
Is nested function a good approach when required by only one function? [closed]
Let's say that a function A is required only by function B , should A be defined inside B?
12 Answers
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Is there a query language for JSON?
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Sure, how about:
JsonPath.
Json Query
They all seem to be a bit work in progress, but work to some degree. They are also similar to XPath and XQuery conceptually; even though XML and JSON have different conceptual models (hierarchic...
Is returning by rvalue reference more efficient?
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Beta_ab&&
Beta::toAB() const {
return move(Beta_ab(1, 1));
}
This returns a dangling reference, just like with the lvalue reference case. After the function returns, the temporary object will get destructed. You...
Getting a list of associative array keys
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You can use: Object.keys(obj)
Example:
var dictionary = {
"cats": [1, 2, 37, 38, 40, 32, 33, 35, 39, 36],
"dogs": [4, 5, 6, 3, 2]
};
// Get the keys
var keys = Object.keys(dictionary);
console.log(keys);
See reference below...
Selecting a row of pandas series/dataframe by integer index
...curious as to why df[2] is not supported, while df.ix[2] and df[2:3] both work.
6 Answers
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What is the difference between char array and char pointer in C?
I am trying to understand pointers in C but I am currently confused with the following:
8 Answers
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