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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?
...
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?
...
iPhone UITextField - Change placeholder text color
...olor blackColor];
textField.attributedPlaceholder = [[NSAttributedString alloc] initWithString:placeholderText attributes:@{NSForegroundColorAttributeName: color}];
} else {
NSLog(@"Cannot set placeholder text's color, because deployment target is earlier than iOS 6.0");
// TODO: Add fall-back...
Using custom std::set comparator
...should use a functor (a class that overloads the () operator so it can be called like a function).
struct lex_compare {
bool operator() (const int64_t& lhs, const int64_t& rhs) const {
stringstream s1, s2;
s1 << lhs;
s2 << rhs;
return s1.str()...
python assert with and without parenthesis
...through IDLE. Because assert is a keyword and not a function, you are actually passing in a tuple as the first argument and leaving off the second argument.
Recall that non-empty tuples evaluate to True, and since the assertion message is optional, you've essentially called assert True when you wr...
How do I convert a Vector of bytes (u8) to a string
...("result: {}", s);
}
The conversion is in-place, and does not require an allocation. You can create a String from the string slice if necessary by calling .to_owned() on the string slice (other options are available).
The library reference for the conversion function:
std::str::from_utf8
...
Asp.NET Web API - 405 - HTTP verb used to access this page is not allowed - how to set handler mappi
...
Common cause for this error is WebDAV. Make sure you uninstall it.
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Random number generator only generating one random number
..., max);
}
}
Edit (see comments): why do we need a lock here?
Basically, Next is going to change the internal state of the Random instance. If we do that at the same time from multiple threads, you could argue "we've just made the outcome even more random", but what we are actually doing is ...
Forward declaring an enum in C++
...can't know the storage required for the enum variable. C++ Compiler's are allowed to specify the actual storage space based on the size necessary to contain all the values specified. If all that is visible is the forward declaration, the translation unit can't know what storage size will have been...