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jQuery Selector: Id Ends With?
...ere a selector that I can query for elements with an ID that ends with a given string?
9 Answers
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Why doesn't the example compile, aka how does (co-, contra-, and in-) variance work?
...iant type parameter is one which is allowed to vary down as the class is subtyped (alternatively, vary with subtyping, hence the "co-" prefix). More concretely:
trait List[+A]
List[Int] is a subtype of List[AnyVal] because Int is a subtype of AnyVal. This means that you may provide an instance ...
How do I get a string format of the current date time, in python?
...>>> import datetime
>>> datetime.date.today().strftime("%B %d, %Y")
'July 23, 2010'
>>> datetime.datetime.now().strftime("%I:%M%p on %B %d, %Y")
'10:36AM on July 23, 2010'
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UIBarButtonItem with custom image and no border
I want to create a UIBarButtonItem with a custom image, but I don't want the border that iPhone adds, as my Image has a special border.
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Set a default parameter value for a JavaScript function
...used if the value isn't defined (and ignored if the value is passed). In Ruby you can do it like this:
27 Answers
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What's better at freeing memory with PHP: unset() or $var = null
... overhead of a function call ( update , is actually a language construct), but it would be interesting to know if one is better than the other. I have been using unset() for most of my coding, but I've recently looked through a few respectable classes found off the net that use $var = null inste...
How do you do a simple “chmod +x” from within python?
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Use os.stat() to get the current permissions, use | to or the bits together, and use os.chmod() to set the updated permissions.
Example:
import os
import stat
st = os.stat('somefile')
os.chmod('somefile', st.st_mode | stat.S_IEXEC)
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How to calculate number of days between two given dates?
If I have two dates (ex. '8/18/2008' and '9/26/2008' ), what is the best way to get the number of days between these two dates?
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What is the Comonad typeclass in Haskell?
...es that provide a Comonad typeclass are also welcome). I've vaguely heard about Comonad, but all I really know about it is that is provides extract :: w a -> a , sort of a parallel to Monad's return :: a -> m a .
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Most efficient way to determine if a Lua table is empty (contains no entries)?
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Your code is efficient but wrong. (Consider {[false]=0}.) The correct code is
if next(myTable) == nil then
-- myTable is empty
end
For maximum efficiency you'll want to bind next to a local variable, e.g.,
...
local next = next
...
... if next(....