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Switch statement fall-through…should it be allowed? [closed]
For as long as I can remember I have avoided using switch statement fall-through. Actually, I can't remember it ever entering my consciousness as a possible way to do things as it was drilled into my head early on that it was nothing more than a bug in the switch statement. However, today I ran acro...
Const in JavaScript: when to use it and is it necessary?
...ently come across the const keyword in JavaScript. From what I can tell, it is used to create immutable variables , and I've tested to ensure that it cannot be redefined (in Node.js):
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Using an HTML button to call a JavaScript function
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There are a few ways to handle events with HTML/DOM. There's no real right or wrong way but different ways are useful in different situations.
1: There's defining it in the HTML:
<input id="clickMe" type="button" value="clickme" onclick="doFunction();" /&g...
How to overload std::swap()
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The right way to overload swap is to write it in the same namespace as what you're swapping, so that it can be found via argument-dependent lookup (ADL). One particularly easy thing to do is:
class X
{
// ...
friend void swap(X& a, X& b)
{
...
How to show Page Loading div until the page has finished loading?
I have a section on our website that loads quite slowly as it's doing some intensive calls.
12 Answers
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Difference between size_t and unsigned int?
...he internet and everywhere mentioned that size_t is an unsigned type so, it can represent only non-negative values.
7 Ans...
Calling virtual functions inside constructors
...l of the hierarchy in the current constructor and no further.
The C++ FAQ Lite covers this in section 23.7 in pretty good detail. I suggest reading that (and the rest of the FAQ) for a followup.
Excerpt:
[...] In a constructor, the virtual call mechanism is disabled because overriding from derived...
Why is there a `null` value in JavaScript?
...ll value in JS" - there is a null value of some sort in most languages and it is generally considered very useful.
The question is, "why is there an undefined value in JS". Major places where it is used:
when you declare var x; but don't assign to it, x holds undefined;
when your function gets fe...
How to truncate a foreign key constrained table?
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You cannot TRUNCATE a table that has FK constraints applied on it (TRUNCATE is not the same as DELETE).
To work around this, use either of these solutions. Both present risks of damaging the data integrity.
Option 1:
Remove constraints
Perform TRUNCATE
Delete manually the rows that n...
What exactly do “IB” and “UB” mean?
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IB: Implementation-defined Behaviour. The standard leaves it up to the particular compiler/platform to define the precise behaviour, but requires that it be defined.
Using implementation-defined behaviour can be useful, but makes your code less portable.
UB: Undefined Behaviour. T...