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Would it be beneficial to begin using instancetype instead of id?
...stancetype that, as far as I can see, replaces id as a return type in -alloc and init .
4 Answers
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How do you get the logical xor of two variables in Python?
...e not comparing apples to oranges, is "if xor( isApple(x), isApple(y) )" really clearer than "if isApple(x) != isApple(y)" ? Not to me!
– AmigoNico
May 21 '12 at 18:27
109
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How do I make a transparent canvas in html5?
...e top layer to transparent at the start of rendering every new frame. I finally found the answer: it's not using globalAlpha, and it's not using a rgba() color. The simple, effective answer is:
context.clearRect(0,0,width,height);
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What's the difference between the build and create methods in FactoryGirl?
...ance of the model while the build() method keeps it only on memory.
Personally, I use the create() method only when persistence is really necessary since writing to DB makes testing time consuming.
e.g.
I create users to authentication with create() because my authentication engine queries the D...
How long is the SHA256 hash?
...(64), or even a char(64), as the length is always the same, not varying at all.
And the demo :
$hash = hash('sha256', 'hello, world!');
var_dump($hash);
Will give you :
$ php temp.php
string(64) "68e656b251e67e8358bef8483ab0d51c6619f3e7a1a9f0e75838d41ff368f728"
i.e. a string with 64 character...
Merge git repo into branch of another repo
...epo Bar. I want to merge Bar with Foo, but only into a separate branch, called baz .
3 Answers
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Why define an anonymous function and pass it jQuery as the argument?
...de demo code from the backbone.js screencasts. In it, the backbone code is all enclosed in an anonymous function that is passed the jQuery object:
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Will the Garbage Collector call IDisposable.Dispose for me?
...lizer, and implement IDisposable, that your finalizer needs to explicitly call Dispose.
This is logical, and is what I've always done in the rare situations where a finalizer is warranted.
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In R, how to get an object's name after it is sent to a function?
...(mean.x)}
test(a)
#[1] "a" ... this is the side-effect of the print() call
# ... you could have done something useful with that character value
#[1] 5.5 ... this is the result of the function call
Edit: Ran it with the new test-object
Note: this will not succeed inside a local func...
What do 'statically linked' and 'dynamically linked' mean?
I often hear the terms 'statically linked' and 'dynamically linked', often in reference to code written in C , C++ or C# . What are they, what exactly are they talking about, and what are they linking?
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