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Should I use an exception specifier in C++?
In C++, you can specify that a function may or may not throw an exception by using an exception specifier. For example:
14 ...
How to print a number with commas as thousands separators in JavaScript
... // * example 11: number_format('1.20', 4);
// * returns 11: '1.2000'
// * example 12: number_format('1.2000', 3);
// * returns 12: '1.200'
var n = !isFinite(+number) ? 0 : +number,
prec = !isFinite(+decimals) ? 0 : Math.abs(decimals),
sep = (typeof thou...
Is there a standard sign function (signum, sgn) in C/C++?
...
Surprised no one has posted the type-safe C++ version yet:
template <typename T> int sgn(T val) {
return (T(0) < val) - (val < T(0));
}
Benefits:
Actually implements signum (-1, 0, or 1). Implementations here using copysign only return -1 or 1, w...
How many and which are the uses of “const” in C++?
As a novice C++ programmer there are some constructs that look still very obscure to me, one of these is const . You can use it in so many places and with so many different effects that is nearly impossible for a beginner to come out alive. Will some C++ guru explain once forever the various uses a...
Declaring pointers; asterisk on the left or right of the space between the type and name? [duplicate
I've seen mixed versions of this in a lot of code. (This applies to C and C++, by the way.) People seem to declare pointers in one of two ways, and I have no idea which one is correct, of if it even matters.
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function declaration isn't a prototype
...arbitrary number of arguments, while int foo(void) accepts 0 arguments. In C++ they mean the same thing. I suggest that you use void consistently when you mean no arguments.
If you have a variable a, extern int a; is a way to tell the compiler that a is a symbol that might be present in a different...
throwing exceptions out of a destructor
...he noexcept(false) so the code keeps its original meaning.
// Post C++11 destructors are by default `noexcept(true)` and
// this will (by default) call terminate if an exception is
// escapes the destructor.
//
// But this example is designed to show that term...
Why is there no std::stou?
C++11 added some new string conversion functions:
3 Answers
3
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What's the fastest way to do a bulk insert into Postgres?
...2, fieldname3)
VALUES (
UNNEST(ARRAY[1, 2, 3]),
UNNEST(ARRAY[100, 200, 300]),
UNNEST(ARRAY['a', 'b', 'c'])
);
without VALUES using subselect with additional existance check:
INSERT INTO tablename (fieldname1, fieldname2, fieldname3)
SELECT * FROM (
SELECT UNNEST(ARRAY[1, 2, 3]),...
How can I check if a value is a json object?
...e: 'json',
// "sucess" will be executed only if the response status is 200 and get a JSON
success: function (json) {},
// "error" will run but receive state 200, but if you miss the JSON syntax
error: function (xhr) {}
});
...