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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...
Reference: What is variable scope, which variables are accessible from where and what are “undefined
...". Just because you wrote $foo = 'bar'; once somewhere in your application doesn't mean you can refer to $foo from everywhere else inside the application. The variable $foo has a certain scope within which it is valid and only code in the same scope has access to the variable.
How is a scope define...
Converting between java.time.LocalDateTime and java.util.Date
...e-zone is not part of the actual state of java.util.Date.
An Instant also does not contain any information about the time-zone. Thus, to convert from an Instant to a local date-time it is necessary to specify a time-zone. This might be the default zone - ZoneId.systemDefault() - or it might be a ti...
Post-install script with Python setuptools
...n even call shell commands during installation, like in this example which does pre-installation preparation:
from setuptools import setup
from setuptools.command.develop import develop
from setuptools.command.install import install
from subprocess import check_call
class PreDevelopCommand(develo...
Pythonic way to print list items
...print(p) for p in myList not working, you can just use the following which does the same thing and is still one line:
for p in myList: print p
For a solution that uses '\n'.join(), I prefer list comprehensions and generators over map() so I would probably use the following:
print '\n'.join(str(p...
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...
Do you (really) write exception safe code? [closed]
...error would go in the "Normal failure vs. bug" section, that is, a bug.
It doesn't invalidate the reasoning, and it does not mean the exception-safe code is useless because impossible to attain.
You can't protect yourself against the computer switching off, or compiler bugs, or even your bugs, or ot...