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What is the difference between HTTP_HOST and SERVER_NAME in PHP?
What is the difference between HTTP_HOST and SERVER_NAME in PHP?
10 Answers
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What exactly do “IB” and “UB” mean?
I've seen the terms "IB" and "UB" used several times, particularly in the context of C++. I've tried googling them, but apparently those two-letter combinations see a lot of use. :P
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What is this crazy C++11 syntax ==> struct : bar {} foo {};?
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First, we'll take a bog-standard abstract UDT (User-Defined Type):
struct foo { virtual void f() = 0; }; // normal abstract type
foo obj;
// error: cannot declare variable 'obj' to be of abstract type 'foo'
Let's also recall that we can instantiate...
Evaluate expression given as a string
...ied. For example, if you have a pre-defined variable name equal to "David" and you reassign using eval(parse(text = "name") == "Alexander", you will get an error because eval & parse do not return an R expression that can be evaluated.
– Crt
Aug 1 '16 at 22...
What is std::move(), and when should it be used?
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Wikipedia Page on C++11 R-value references and move constructors
In C++11, in addition to copy constructors, objects can have move constructors.
(And in addition to copy assignment operators, they have move assignment operators.)
The move constructor is used instead...
What are the disadvantages to declaring Scala case classes?
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First the good bits:
Everything immutable by default
Yes, and can even be overridden (using var) if you need it
Getters automatically defined
Possible in any class by prefixing params with val
Decent toString() implementation
Yes, very useful, but doable by hand on any class if nece...
Is it possible to make a type only movable and not copyable?
...ntation.
To answer the question you didn't ask... "what's up with moves and copy?":
Firstly I'll define two different "copies":
a byte copy, which is just shallowly copying an object byte-by-byte, not following pointers, e.g. if you have (&usize, u64), it is 16 bytes on a 64-bit computer, ...
Converting Long to Date in Java returns 1970
...time as long in milliseconds, not seconds. You need to multiply it by 1000 and make sure that you supply it as long.
Date d = new Date(1220227200L * 1000);
This shows here
Sun Aug 31 20:00:00 GMT-04:00 2008
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Which is preferred: Nullable.HasValue or Nullable != null?
...eal difference. Just do whichever is more readable/makes more sense to you and your colleagues.
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What is the difference between `-fpic` and `-fPIC` gcc parameters?
I've already read the gcc manpage, but I still can't understand the difference between -fpic and -fPIC . Can someone explain it, in a very simple and clear way?
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