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What would a “frozen dict” be?
...).
The most common reason to want such a type is when memoizing function calls for functions with unknown arguments. The most common solution to store a hashable equivalent of a dict (where the values are hashable) is something like tuple(sorted(kwargs.iteritems())).
This depends on the sorting n...
Can “using” with more than one resource cause a resource leak?
...
No.
The compiler will generate a separate finally block for each variable.
The spec (§8.13) says:
When a resource-acquisition takes the form of a
local-variable-declaration, it is possible to acquire multiple
resources of a given type. A using statement of the...
How to make a cross-module variable?
...as if a global from any other module that includes __builtin__ -- which is all of them, by default.
a.py contains
print foo
b.py contains
import __builtin__
__builtin__.foo = 1
import a
The result is that "1" is printed.
Edit: The __builtin__ module is available as the local symbol __builtin...
What does pylint's “Too few public methods” message mean
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The error basically says that classes aren't meant to just store data, as you're basically treating the class as a dictionary. Classes should have at least a few methods to operate on the data that they hold.
If your class looks like this:...
Regex lookahead, lookbehind and atomic groups
...ely follow, and stop as backtracking is disabled
A non-atomic group will allow backtracking; if subsequent matching ahead fails, it will backtrack and use alternative patterns until a match for the entire expression is found or all possibilities are exhausted.
(foo|foot)s applied to foots will:
...
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
1
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Referring to the null object in Python
...
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...
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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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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