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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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CSV API for Java [closed]
Can anyone recommend a simple API that will allow me to use read a CSV input file, do some simple transformations, and then write it.
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Cleaner way to update nested structures
...scalaz.TreeLoc). It turns out that the structure of the zipper is automatically derivable from the original data structure, in a manner that resembles symbolic differentiation of an algebraic expression.
But how does this help you with your Scala case classes? Well, Lukas Rytz recently prototyped a...
How to pass a class type as a function parameter
...lass: AnyClass = type(of: self)
Swift 2.x
let myClass: AnyClass = object_getClass(self)
and you can pass it as paramater later, if you'd like.
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Find first element by predicate
...e stream. It's an intermediate operation, which returns a lazy stream (actually all intermediate operations return a lazy stream). To convince you, you can simply do the following test:
List<Integer> list = Arrays.asList(1, 10, 3, 7, 5);
int a = list.stream()
.peek(num -> Syste...
jQuery Selector: Id Ends With?
...:inpTest"). This does not $("[id$='inpTest']"). Is it because colon is not allowed in ID (but JSF adds it!)?
– Panu Haaramo
Apr 26 '14 at 10:16
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CSS Selector “(A or B) and C”?
... syntax?
No. CSS' or operator (,) does not permit groupings. It's essentially the lowest-precedence logical operator in selectors, so you must use .a.c,.b.c.
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How do I sort a dictionary by value?
...(x.items(), key=operator.itemgetter(0))
In Python3 since unpacking is not allowed [1] we can use
x = {1: 2, 3: 4, 4: 3, 2: 1, 0: 0}
sorted_x = sorted(x.items(), key=lambda kv: kv[1])
If you want the output as a dict, you can use collections.OrderedDict:
import collections
sorted_dict = collection...
How to “test” NoneType in python?
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It can also be done with isinstance as per Alex Hall's answer :
>>> NoneType = type(None)
>>> x = None
>>> type(x) == NoneType
True
>>> isinstance(x, NoneType)
True
isinstance is also intuitive but there is the complication that it re...
Better to 'try' something and catch the exception or test if it's possible first to avoid an excepti
...est option when the index is probably in the list and the IndexError is usually not raised. This way you avoid the need for an extra lookup by if index < len(my_list).
Python encourages the use of exceptions, which you handle is a phrase from Dive Into Python. Your example not only handles the e...