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Why create “Implicitly Unwrapped Optionals”, since that implies you know there's a value?
... var button: UIButton!
var buttonOriginalWidth: CGFloat!
override func awakeFromNib() {
self.buttonOriginalWidth = self.button.frame.size.width
}
}
Here, you cannot calculate the original width of the button until the view loads, but you know that awakeFromNib will be called b...
How do I replace NA values with zeros in an R dataframe?
...ce(., is.na(.), 0))
The Complete Analysis -
Updated for dplyr 0.8.0: functions use purrr format ~ symbols: replacing deprecated funs() arguments.
Approaches tested:
# Base R:
baseR.sbst.rssgn <- function(x) { x[is.na(x)] <- 0; x }
baseR.replace <- function(x) { replace(x, is...
How do I browse an old revision of a Subversion repository through the web view?
... querystring.
i.e. http://trac.example.com/log/trunk/client/filename?rev=123
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Python, remove all non-alphabet chars from string
...
123
Use re.sub
import re
regex = re.compile('[^a-zA-Z]')
#First parameter is the replacement, se...
Can you autoplay HTML5 videos on the iPad?
...
<video autoplay loop muted playsinline>
<source src="video.mp4?123" type="video/mp4">
</video>
<script type="text/javascript">
$(function () {
if (!navigator.userAgent.match(/(iPod|iPhone|iPad)/)) {
$("video").prop('muted', false);
}
});
</script>
...
?: operator (the 'Elvis operator') in PHP
...lse ?: 0); // 0
var_dump(null ?: 'foo'); // 'foo'
var_dump(true ?: 123); // true
var_dump('rock' ?: 'roll'); // 'rock'
?>
By the way, it's called the Elvis operator.
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How is Math.Pow() implemented in .NET Framework?
... things up, I decided to take a look at the implementation of Math.Pow() function. But in .NET Reflector , all I found was this:
...
What is the best django model field to use to represent a US dollar amount?
...s automatically from templates:
{{ somemodel.some_currency }}
Output:
$123.00
It has a powerful backend via python-money and it's essentially a drop-in replacement for standard decimal fields.
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Declare a constant array
...
Just for clarification: the [...]T syntax is sugar for [123]T. It creates a fixed size array, but lets the compiler figure out how many elements are in it.
– jimt
Oct 30 '12 at 11:21
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Haskell: Lists, Arrays, Vectors, Sequences
... standard library, and for that matter the prelude, is full of useful list functions that should litter your code (foldr,map,filter). Lists are persistant , aka purely functional, which is very nice. Haskell lists aren't really "lists" because they are coinductive (other languages call these strea...