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What does “where T : class, new()” mean?
...constraint on the generic parameter T. It must be a class (reference type) and must have a public parameter-less default constructor.
That means T can't be an int, float, double, DateTime or any other struct (value type).
It could be a string, or any other custom reference type, as long as it has ...
When to make a type non-movable in C++11?
...x objects. If std::mutex contained a native OS mutex type as a data member and the native type's address must stay fixed (because the OS maintains a list of pointers to its mutexes) then either std::mutex would have to store the native mutex type on the heap so it would stay at the same location whe...
How to write a large buffer into a binary file in C++, fast?
I'm trying to write huge amounts of data onto my SSD(solid state drive). And by huge amounts I mean 80GB.
12 Answers
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How do I use cascade delete with SQL Server?
I have 2 tables: T1 and T2, they are existing tables with data. We have a one to many relationship between T1 and T2. How do I alter the table definitions to perform cascading delete in SQL Server when a record from T1 is deleted, all associated records in T2 also deleted.
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Automatically create an Enum based on values in a database lookup table?
How do I automatically create an enum and subsequently use its values in C# based on values in a database lookup table (using enterprise library data layer)?
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Why isn't vector a STL container?
... &x = b[5]; // that's what really happens
bool y = b[5]; // implicitly converted to bool
assert(b[5] == false); // converted to bool
assert(b[6] == b[7]); // bool operator==(const reference &, const reference &);
b[5] = true; // assignment on reference
assert(b[5] == true); // and actua...
Is it OK to use == on enums in Java?
...
Just my 2 cents: Here is the code for Enum.java, as published by Sun, and part of the JDK:
public abstract class Enum<E extends Enum<E>>
implements Comparable<E>, Serializable {
// [...]
/**
* Returns true if the specified object is equal to this
* enu...
Big O, how do you calculate/approximate it?
Most people with a degree in CS will certainly know what Big O stands for .
It helps us to measure how well an algorithm scales.
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When should I use C++14 automatic return type deduction?
...11 raises similar questions: when to use return type deduction in lambdas, and when to use auto variables.
The traditional answer to the question in C and C++03 has been "across statement boundaries we make types explicit, within expressions they are usually implicit but we can make them explicit w...
When is -XAllowAmbiguousTypes appropriate?
...er non-ambiguous types. So let's compare the contexts of the two functions and look for functional dependencies.
class ApplySym sig f sym | sig sym -> f, f -> sig sym
class SyntacticN f internal | f -> internal
sugarSym :: ( sub :<: AST sup
, ApplySym sig fi sup
...