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Why is there a `null` value in JavaScript?
.... (3) should really throw an exception straight away, and the fact that it doesn't, instead of returning this weird undefined that will fail later, is a big source of debugging difficulty.
*: you could also argue that (2) should throw an exception, but then you'd have to provide a better, more expl...
Clone() vs Copy constructor- which is recommended in java [duplicate]
... THE CLONE METHOD of the Object class
is a somewhat magical method that does
what no pure Java method could ever
do: It produces an identical copy of
its object. It has been present in the
primordial Object superclass since the
Beta-release days of the Java
compiler*; and it, like all...
How to dismiss a Twitter Bootstrap popover by clicking outside?
... I attach to $(document) instead of $('body') since sometimes the body doesn't extend down the entire page.
– jasop
Jul 5 '13 at 15:10
6
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Efficient way to return a std::vector in c++
...ctor<int> myvec;
... some time later ...
myvec = f();
Copy elision does not prevent a copy here because it's an assignment rather than an initialization. However, you should still return by value. In C++11, the assignment is optimized by something different, called "move semantics". In C++03...
Are Exceptions in C++ really slow
...e when no exceptions occur
it costs around 10x/20x an if when an exception does occur
The cost, however, is not trivial to measure:
The side-table is generally cold, and thus fetching it from memory takes a long time
Determining the right handler involves RTTI: many RTTI descriptors to fetch, sc...
Assigning default values to shell variables with a single command in bash
...
It turns out THIS DOES NOT ALWAYS WORK FOR BASH-BUILTIN VARIABLES. It's very very weird. Currently those known to me are HISTTIMEFORMAT
– Otheus
Apr 13 '16 at 10:20
...
Difference between single and double square brackets in Bash
...
I'd add that if your script doesn't start with a shebang that explicitly requests a shell that supports [[ ]] (e.g. bash with #!/bin/bash or #!/usr/bin/env bash), you should use the portable option. Scripts that assume /bin/sh supports extensions like t...
Get an object's class name at runtime
...
Unfortunately MyClass.name is an ES6 feature hence it does not work in IE11.
– begie
May 9 '16 at 15:30
9
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Collections.emptyMap() vs new HashMap()
...e an API where clients are expected to modify the collection, then yes, it does not make sense to return an immutable collection. But if you have an API where you return a collection that clients must not modify and should just iterate on, then returning a view to the underlying collection makes per...