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How does the new automatic reference counting mechanism work?
...rty assignments are inexpensive (as discussed here). I know I'm replacing all of my existing Mac GC code with ARC implementations.
As to whether this could be extended to other languages, it seems geared around the reference counting system in Objective-C. It might be difficult to apply this to J...
Is inline assembly language slower than native C++ code?
...
Yes, most times.
First of all you start from wrong assumption that a low-level language (assembly in this case) will always produce faster code than high-level language (C++ and C in this case). It's not true. Is C code always faster than Java code? N...
Why should I use Google's CDN for jQuery?
...
This is because:
It increases the parallelism available. (Most browsers will only download 3 or 4 files at a time from any given site.)
It increases the chance that there will be a cache-hit. (As more sites follow this practice, more users already have the fil...
xUnit.net: Global setup + teardown?
... protected TestsBase()
{
// Do "global" initialization here; Called before every test method.
}
public void Dispose()
{
// Do "global" teardown here; Called after every test method.
}
}
public class DummyTests : TestsBase
{
// Add test methods
}
However, ...
HTML5: number input type that takes only integers?
...ields are signed floating-point numbers (for unsigned ints you'll have to fall back to "pattern" validation and thus lose extra features like the up and down arrows for browsers that support it). Is there another input type or perhaps an attribute that would restrict the input to just unsigned integ...
How can I use interface as a C# generic type constraint?
...nHolt: I think think the creators of .NET, in deciding what constraints to allow, were focused on ones that would let generic classes and methods do things with generic types that they otherwise could not, rather than on preventing them from being used in nonsensical ways. That having been said, an...
CHECK constraint in MySQL is not working
...ySQL Reference Manual says:
The CHECK clause is parsed but ignored by all storage engines.
Try a trigger...
mysql> delimiter //
mysql> CREATE TRIGGER trig_sd_check BEFORE INSERT ON Customer
-> FOR EACH ROW
-> BEGIN
-> IF NEW.SD<0 THEN
-> SET NEW.SD=0;...
Length of a JavaScript object
...an break enumerations in various libraries. Adding methods to Object is usually safe, though.
Here's an update as of 2016 and widespread deployment of ES5 and beyond. For IE9+ and all other modern ES5+ capable browsers, you can use Object.keys() so the above code just becomes:
var size = Object...
git reset --hard HEAD leaves untracked files behind
...rking copy.
If you need to reset the whole repository to master including all git submodules, run this script:
git reset --hard HEAD
git clean -f -d
git checkout master
git fetch origin master
git reset --hard origin/master
git pull
git submodule update
git submodule update --init --recursive
git ...
Differences between Perl and PHP [closed]
...ype, of which Perl has three, and the type specifier is part of the name (called a "sigil"), so $foo is a different variable than @foo or %foo.
(related to the previous point) Perl has separate symbol table entries for scalars, arrays, hashes, code, file/directory handles and formats. Each has its o...