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Declaring variables inside or outside of a loop
...that str absolutely ought to be declared within the while loop. No ifs, no ands, no buts.
The only case where this rule might be violated is if for some reason it is of vital importance that every clock cycle must be squeezed out of the code, in which case you might want to consider instantiating s...
What exactly is a reentrant function?
...rant?
No.
For example, let's have a C++ function that takes both a lock, and a callback as a parameter:
#include <mutex>
typedef void (*callback)();
std::mutex m;
void foo(callback f)
{
m.lock();
// use the resource protected by the mutex
if (f) {
f();
}
// u...
How to install a gem or update RubyGems if it fails with a permissions error
... using gem install mygem or update RubyGems using gem update --system , and it fails with this error:
27 Answers
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Volatile vs Static in Java
...t correct to say that static means one copy of the value for all objects and volatile means one copy of the value for all threads?
...
Using jQuery to compare two arrays of Javascript objects
...that I'd like to compare to see if they are the same. The objects may not (and most likely will not) be in the same order in each array. Each array shouldn't have any more than 10 objects. I thought jQuery might have an elegant solution to this problem, but I wasn't able to find much online.
...
How to use filter, map, and reduce in Python 3
filter , map , and reduce work perfectly in Python 2. Here is an example:
7 Answers
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Disable same origin policy in Chrome
...
Close chrome (or chromium) and restart with the --disable-web-security argument. I just tested this and verified that I can access the contents of an iframe with src="http://google.com" embedded in a page served from "localhost" (tested under chromium ...
What is the purpose of .PHONY in a Makefile?
...e used to build files from other files. Make assumes its target is a file, and this makes writing Makefiles relatively easy:
foo: bar
create_one_from_the_other foo bar
However, sometimes you want your Makefile to run commands that do not represent physical files in the file system. Good example...
When to delete branches in Git?
...ges (ie, you would lose commits by deleting the branch), git will tell you and won't delete it.
So, deleting a merged branch is cheap and won't make you lose any history.
To delete a remote branch, use git push origin :mybranch, assuming your remote name is origin and the remote branch you want do...
Using the “final” modifier whenever applicable in Java [closed]
...eywords in your code, but pretty soon you'll stop noticing the word itself and will simply think, that-thing-will-never-change-from-this-point-on (you can take it from me ;-)
I think it's good practice. I am not using it all the time, but when I can and it makes sense to label something final I'll ...