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What is the 'new' keyword in JavaScript?
...n's external, accessible, prototype object (every function object automatically has a prototype property).
It makes the this variable point to the newly created object.
It executes the constructor function, using the newly created object whenever this is mentioned.
It returns the newly created objec...
Why is Python 3.x's super() magic?
In Python 3.x, super() can be called without arguments:
1 Answer
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Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
Rails 3.1: Engine vs. Mountable App
...s, someone please let me know and I'll fix this response. I have made a small article about the subject here Cheers!
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How to “perfectly” override a dict?
...or other builtins) directly. It often makes no sense, because what you actually want to do is implement the interface of a dict. And that is exactly what ABCs are for.
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Is this the right way to clean-up Fragment back stack when leaving a deeply nested stack?
...out this depending on the intended behavior, but this link should give you all the best solutions and not surprisingly is from Dianne Hackborn
http://groups.google.com/group/android-developers/browse_thread/thread/d2a5c203dad6ec42
Essentially you have the following options
Use a name for your in...
How can I join elements of an array in Bash?
... +1. What about printf -v bar ",%s" "${foo[@]}". It is one fork less (actually clone). It is even forking reading a file: printf -v bar ",%s" $(<infile).
– TrueY
Jun 8 '13 at 22:55
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How to list all the files in a commit?
...ooking for a simple git command that provides a nicely formatted list of all files that were part of the commit given by a hash (SHA1), with no extraneous information.
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Calling a function of a module by using its name (a string)
What is the best way to go about calling a function given a string with the function's name in a Python program. For example, let's say that I have a module foo , and I have a string whose content is "bar" . What is the best way to call foo.bar() ?
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partial string formatting
...ct):
def __missing__(self, key):
return "{" + key + "}"
s = '{foo} {bar}'
formatter = string.Formatter()
mapping = FormatDict(foo='FOO')
print(formatter.vformat(s, (), mapping))
printing
FOO {bar}
Of course this basic implementation only works correctly for basic cases.
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