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recursion versus iteration
...w the return back to the caller functions. In many cases, memory has to be allocated and copied to implement scope isolation.
Some optimizations, like tail call optimization, make recursions faster but aren't always possible, and aren't implemented in all languages.
The main reasons to use recursi...
In Clojure, when should I use a vector over a list, and the other way around?
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Vectors have O(1) random access times, but they have to be preallocated. Lists can be dynamically extended, but accessing a random element is O(n).
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Get size of all tables in database
... i.object_id = p.OBJECT_ID AND i.index_id = p.index_id
INNER JOIN
sys.allocation_units a ON p.partition_id = a.container_id
LEFT OUTER JOIN
sys.schemas s ON t.schema_id = s.schema_id
WHERE
t.NAME NOT LIKE 'dt%'
AND t.is_ms_shipped = 0
AND i.OBJECT_ID > 255
GROUP BY
t...
What is a C++ delegate?
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std::function doesn't always dynamically allocate
– Lightness Races in Orbit
Jul 13 '19 at 14:56
3
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Why should I prefer to use member initialization lists?
...le, but imagine if you will that A's default constructor did more, such as allocating memory or opening files. You wouldn't want to do that unnecessarily.
Furthermore, if a class doesn't have a default constructor, or you have a const member variable, you must use an initializer list:
class A
{
p...
What is the difference between Digest and Basic Authentication?
...and a secret.
The Bearer scheme is dedicated to the authentication using a token.
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Create a list from two object lists with linq
...ed execution, using Concat would likely be faster because it avoids object allocation - Concat doesn't copy anything, it just creates links between the lists so when enumerating and you reach the end of one it transparently takes you to the start of the next! This is my point.
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Can't use Swift classes inside Objective-C
...}
}
Objective-C code (calling code)
SwiftClass *obj = [[SwiftClass alloc] initWithStringValue: @"Hello World!"];
[obj printValue];
NSString * str = obj.stringValue;
obj.stringValue = @"HeLLo wOrLd!!!";
Result
4. Call Objective-c class from Swift code
Objective-C class (ObjcClass.h)
#impo...
Why does sizeof(x++) not increment x?
...untime. (Note: Variable Length Arrays are a specific feature -- not arrays allocated with malloc(3).) Otherwise, only the type of the expression is computed, and that at compile time.
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How to avoid overflow in expr. A * B - C * D
... Both long long and double are 64 bits. Since double has to allocate some bits for the exponent, it has a smaller range of possible values without loss of precision.
– Jim Garrison
Nov 5 '12 at 19:03
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