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Why do we use __init__ in Python classes?
...Spot is a bit of a cripple and is mostly yellow. The __init__ function is called a constructor, or initializer, and is automatically called when you create a new instance of a class. Within that function, the newly created object is assigned to the parameter self. The notation self.legs is an attrib...
What are the differences between “generic” types in C++ and Java?
...+" operator available.
In Java you have to specify a type if you want to call methods on the objects passed, something like:
<T extends Something> T sum(T a, T b) { return a.add ( b ); }
In C++ generic functions/classes can only be defined in headers, since the compiler generates different...
How can I export tables to Excel from a webpage [closed]
... can I export tables to Excel from a webpage. I want the export to contain all the formatting and colours.
14 Answers
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What exactly is a Context in Java? [duplicate]
...'s ApplicationContext, Android's Context, JNDI's InitialContext, etc. They all often follow the Facade Pattern which abstracts the environmental details the enduser doesn't need to know about away in a single interface/class.
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What are the advantages of using a schema-free database like MongoDB compared to a relational databa
...ire several tables to properly represent in a relational db. This is especially useful if your data is immutable.
Deep query-ability. MongoDB supports dynamic queries on documents using a document-based query language that's nearly as powerful as SQL.
No schema migrations. Since MongoDB is schema-...
Why doesn't nodelist have forEach?
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NodeList now has forEach() in all major browsers
See nodeList forEach() on MDN.
Original answer
None of these answers explain why NodeList doesn't inherit from Array, thus allowing it to have forEach and all the rest.
The answer is found on this es-discus...
How do malloc() and free() work?
I want to know how malloc and free work.
13 Answers
13
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What does O(log n) mean exactly?
...g that the size of the input affects the growth of the algorithm proportionally...and the same goes for, for example, quadratic time O(n2) etc..even algorithms, such as permutation generators, with O(n!) times, that grow by factorials.
...
The necessity of hiding the salt for a hash
...n use something like a user name or phone number to salt the hash. Essentially something that is different for each user but is readily available to us. The other product randomly generates a salt for each user and changes each time the user changes the password. The salt is then encrypted in the...
What is the best way to detect a mobile device?
...igator.userAgent.toLowerCase()));
Now $.browser will return "device" for all above devices
Note: $.browser removed on jQuery v1.9.1. But you can use this by using jQuery migration plugin Code
A more thorough version:
var isMobile = false; //initiate as false
// device detection
if(/(android|b...