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Why can't I use a list as a dict key in python?
..., with the hash as, say, their memory location?
It can be done without really breaking any of the requirements, but it leads to unexpected behavior. Lists are generally treated as if their value was derived from their content's values, for instance when checking (in-)equality. Many would - underst...
Getting started with Haskell
...'ve done this by reading tutorials and watching screencasts, but nothing really seems to stick.
Now, in learning various imperative/OO languages (like C, Java, PHP), exercises have been a good way for me to go. But since I don't really know what Haskell is capable of and because there are many new c...
Determine the type of an object?
...object, and isinstance() to check an object’s type against something. Usually, you want to use isistance() most of the times since it is very robust and also supports type inheritance.
To get the actual type of an object, you use the built-in type() function. Passing an object as the only param...
jQuery or CSS selector to select all IDs that start with some string [duplicate]
How can I select all elements whose id starts with "player_"?
4 Answers
4
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How do I add multiple arguments to my custom template filter in a django template?
...
It is possible and fairly simple.
Django only allows one argument to your filter, but there's no reason you can't put all your arguments into a single string using a comma to separate them.
So for example, if you want a filter that checks if variable X is in the list [1...
Getting SyntaxError for print with keyword argument end=' '
...print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to print with a tuple as argument.
That's obviously bad syntax (literals don't take keyword arguments). In Python 3.x print is an actual function, so it takes keyword arguments, too.
The correct idiom in Python 2.x for ...
What are rvalues, lvalues, xvalues, glvalues, and prvalues?
...e they needed? Probably not if we wish to forfeit the new features. But to allow better optimization we should probably embrace them.
Quoting n3055:
An lvalue (so-called, historically,
because lvalues could appear on the
left-hand side of an assignment
expression) designates a function or
an obj...
Linux反编译全攻略 - 操作系统(内核) - 清泛网 - 专注C/C++及内核技术
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00000110 55 50 58 20 54 65 61 6D 2E 20 41 6C 6C 20 52 69 UPX Team. All Ri
00000120 67 68 74 73 20 52 65 73 65 72 76 65 64 2E 20 24 ghts Reserved. $
从上面的信息中可以看到程序被UPX压缩了，接下来请确信你系统中已有UPX，如果没有请到上面给...
Getters \ setters for dummies
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Isnt it really painful that MS does not support JS correctly and they do not make their silverlight run everywhere, so I have to program everything twice, one for SL and one for rest of the world :)
– Akash Kava
...
How to list all properties of a PowerShell object
...nstructions that can affect either the table or list formats. These are usually meant to limit the display of reams of properties down to just the essential properties. However there are times when you really want to see everything. In those cases Format-List * will show all the properties. Note tha...