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Why is Multiple Inheritance not allowed in Java or C#?
I know that multiple inheritance is not allowed in Java and C#. Many books just say, multiple inheritance is not allowed. But it can be implemented by using interfaces. Nothing is discussed about why it is not allowed. Can anybody tell me precisely why it is not allowed?
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How to get database structure in MySQL via query
... a look at the INFORMATION_SCHEMA.TABLES table. It contains metadata about all your tables.
Example:
SELECT * FROM `INFORMATION_SCHEMA`.`TABLES`
WHERE TABLE_NAME LIKE 'table1'
The advantage of this over other methods is that you can easily use queries like the one above as subqueries in your oth...
How to install lxml on Ubuntu
I'm having difficulty installing lxml with easy_install on Ubuntu 11.
11 Answers
11
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Seeding the random number generator in Javascript
...nswered Feb 6 '09 at 17:42
PeterAllenWebbPeterAllenWebb
9,24833 gold badges3434 silver badges4444 bronze badges
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Why call git branch --unset-upstream to fixup?
.... Once local branch L is set to track remote-tracking branch R, Git will call R its "upstream" and tell you whether you're "ahead" and/or "behind" the upstream (in terms of commits). It's normal (even recommend-able) for the local branch and remote-tracking branches to use the same name (except fo...
setuptools vs. distutils: why is distutils still a thing?
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Have a look at this SO question. It explains all the packaging methods very well, and might help answer your question to some extent: Differences between distribute, distutils, setuptools and distutils2?
Distutils is still the standard tool for packaging in Python. ...
Is pass-by-value a reasonable default in C++11?
...by value into functions and methods is slow for large objects, and is generally frowned upon. Instead, C++ programmers tend to pass references around, which is faster, but which introduces all sorts of complicated questions around ownership and especially around memory management (in the event that ...
Creating an abstract class in Objective-C
I'm originally a Java programmer who now works with Objective-C. I'd like to create an abstract class, but that doesn't appear to be possible in Objective-C. Is this possible?
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Array vs. Object efficiency in JavaScript
...an array, too:
var a3 = [];
a3[29938] = "a";
a3[32994] = "b";
It's basically an array with holes in it, because every array does have continous indexing. It's slower than arrays without holes. But iterating manually through the array is even slower (mostly).
This is an object:
var a3 = {};
a3[2...
When to use virtual destructors?
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Virtual destructors are useful when you might potentially delete an instance of a derived class through a pointer to base class:
class Base
{
// some virtual methods
};
class Derived : public Base
{
~Derived()
{
// Do some important cleanup
}
};
Her...