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How can I count the occurrences of a list item?
...1, 4, 1].count(1)
3
Don't use this if you want to count multiple items. Calling count in a loop requires a separate pass over the list for every count call, which can be catastrophic for performance. If you want to count all items, or even just multiple items, use Counter, as explained in the othe...
Hidden features of Perl?
What are some really useful but esoteric language features in Perl that you've actually been able to employ to do useful work?
...
Python None comparison: should I use “is” or ==?
...ject None, so when you do my_var is None, you're checking whether they actually are the same object (not just equivalent objects)
In other words, == is a check for equivalence (which is defined from object to object) whereas is checks for object identity:
lst = [1,2,3]
lst == lst[:] # This is Tr...
How to use pull to refresh in Swift?
...lf.tableView.reloadData() and self.refreshControl?.endRefreshing() in the callback?
– Qian Chen
Dec 6 '15 at 19:58
Exa...
Android OpenGL ES and 2D
...ur canvas with the proper GL flags for 2D (sprite) rendering.
You should really take a look at SpriteMethodTest by the same author of replica island: http://code.google.com/p/apps-for-android/source/browse/trunk/SpriteMethodTest
See this question where I posted my own code: Using OpenGL to replace ...
Check if a value is within a range of numbers
...u're asking a question about numeric comparisons, so regular expressions really have nothing to do with the issue. You don't need "multiple if" statements to do it, either:
if (x >= 0.001 && x <= 0.009) {
// something
}
You could write yourself a "between()" function:
function b...
What is the curiously recurring template pattern (CRTP)?
... curiously recurring, isn't it? :)
Now, what does this give you? This actually gives the X template the ability to be a base class for its specializations.
For example, you could make a generic singleton class (simplified version) like this
template <class ActualClass>
class Singleton
{
...
How do I size a UITextView to its content?
... Tested on iOS 7 to resize an UITextView into an UITableViewCell. Works really great. This is the only answer that finally worked for me. Thanks!
– Alex
Nov 30 '13 at 18:40
39
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What's the (hidden) cost of Scala's lazy val?
...nswered Jun 15 '10 at 7:51
oxbow_lakesoxbow_lakes
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JavaScript listener, “keypress” doesn't detect backspace?
...s invoked only for character (printable) keys, KeyDown event is raised for all including nonprintable such as Control, Shift, Alt, BackSpace, etc.
UPDATE:
The keypress event is fired when a key is pressed down and that key normally produces a character value
Reference.
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