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How to exit an if clause
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(This method works for ifs, multiple nested loops and other constructs that you can't break from easily.)
Wrap the code in its own function. Instead of break, use return.
Example:
def some_function():
if condition_a:
# do something and return early
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Typedef function pointer?
I'm learning how to dynamically load DLL's but what I don't understand is this line
6 Answers
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Override devise registrations controller
... # add custom create logic here
end
def update
super
end
end
And then tell devise to use that controller instead of the default with:
# app/config/routes.rb
devise_for :users, :controllers => {:registrations => "registrations"}
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Which is more efficient, a for-each loop, or an iterator?
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If you are just wandering over the collection to read all of the values, then there is no difference between using an iterator or the new for loop syntax, as the new syntax just uses the iterator underwater.
If however, you mean by loop the ...
Do unix timestamps change across timezones?
...sents a moment that is the same everywhere. Of course you can convert back and forth to a local timezone representation (time 1397484936 is such-and-such local time in New York, or some other local time in Djakarta) if you want.
The article at http://en.wikipedia.org/wiki/Unix_time is pretty impres...
Should I use s and s inside my s?
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the nav element and the list provide different semantical information:
The nav element communicates that we're dealing with a major navigation block
The list communicates that the links inside this navigation block form a list of items
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How to format a number as percentage in R?
...scales package, as documented in krlmlr's answer. Use that instead of my hand-rolled solution.
Try something like
percent <- function(x, digits = 2, format = "f", ...) {
paste0(formatC(100 * x, format = format, digits = digits, ...), "%")
}
With usage, e.g.,
x <- c(-1, 0, 0.1, 0.5555...
Is the order of iterating through std::map known (and guaranteed by the standard)?
...te from std::map::begin() to std::map::end() using a for , does the standard guarantee that I'll iterate consequently through the elements with keys, sorted in ascending order?
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Is it expensive to use try-catch blocks even if an exception is never thrown?
...rown, it now does a relatively expensive operation of walking up the stack and seeing if any try blocks exist that would catch this exception. From a layman's perspective, try may as well be free. It's actually throwing the exception that costs you - but unless you're throwing hundreds or thousands ...
Remove header and footer from window.print()
I am using window.print() for printing page, but I got header and footer contains page title, file path, page number and date. How to remove them?
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