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How is null + true a string?
...t's walk through this in turn.
X is the null type here - or not a type at all, if you want to think of it that way. It's not providing any candidates. Y is bool, which doesn't provide any user-defined + operators. So the first step finds no user-defined operators.
The compiler then moves on to the...
A cron job for rails: best practices?
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I'm using the rake approach (as supported by heroku)
With a file called lib/tasks/cron.rake ..
task :cron => :environment do
puts "Pulling new requests..."
EdiListener.process_new_messages
puts "done."
end
To execute from the command line, this is just "rake cron". This command ...
Can't use Swift classes inside Objective-C
... -Swift.h file, only the bridging headers. So I created it, but it's actually empty.
I can use all my ObjC classes in Swift, but I can't do it vice versa. I marked my swift class with @objc but it didn't help. What can I do now?
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Lua简明教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ble来管理全局变量的，Lua把这些全局变量放在了一个叫“_G”的Table里。
我们可以用如下的方式来访问一个全局变量（假设我们这个全局变量名叫globalVar）：
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_G.globalVar
_G["globalVar"]
我们可...
Using PHP with Socket.io
...t there are some ways to implement WebSockets. There is this jQuery plugin allowing you to use Websockets while gracefully degrading for non-supporting browsers. On the PHP side, there is this class which seems to be the most widely used for PHP WS servers.
...
Static methods in Python?
Is it possible to have static methods in Python which I could call without initializing a class, like:
10 Answers
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How to refer to relative paths of resources when working with a code repository
...Try to use a filename relative to the current files path. Example for './my_file':
fn = os.path.join(os.path.dirname(__file__), 'my_file')
In Python 3.4+ you can also use pathlib:
fn = pathlib.Path(__file__).parent / 'my_file'
...
Python “raise from” usage
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The difference is that when you use from, the __cause__ attribute is set and the message states that the exception was directly caused by. If you omit the from then no __cause__ is set, but the __context__ attribute may be set as well, and the traceback then shows the co...
What's the yield keyword in JavaScript?
...O.
The function containing the yield keyword is a generator. When you call it, its formal parameters are bound to actual arguments, but its body isn't actually evaluated. Instead, a generator-iterator is returned. Each call to the generator-iterator's next() method performs another pass through ...
Alternative to itoa() for converting integer to string C++? [duplicate]
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I suppose you mean: cppreference.com/cppsstream/all.html
– Wodin
Dec 15 '10 at 9:07
strings...